Abstract booklet (777 kB)

Conférence annuelle sur les

matériaux fonctionnels

3 et 4 mai 2016, à l’ÉTS (1100, rue Notre-Dame

Ouest), Montréal

Advanced Materials

Annual Conference

May 3 and 4, 2016 at ETS 1100, rue Notre-Dame Ouest

Montreal

Commanditaires/Sponsors

Remerciements/Acknowledgements

• France Ortolano (École de technologie supérieure) Secrétaire de direction, Décanat de la recherche/Secretary to the director, Dean of Research

• Rolf Schmidt (Concordia University), CSACS/CRMAA web master

• Philippe Dufour (Université Laval), Agent de liaison scientifique/Scientific liaison officer

• Robert Gauvin (Université Laval), Directeur, Affaires scientifiques et développement/ Director, Scientific affairs and development

• Petr Fiurasek (McGill University), coordonnateur du CRMAA/CSACS coordinator

• Theo van de Ven (McGill University), directeur du CRMAA/CSACS director

• Armand Soldera (Université de Sherbrooke), directeur du CQMF/CQMF director

Horaire/Schedule Mardi, 3 mai 2016/Tuesday, May 3, 2016

Matin/Morning 8:00 - 9:00 Accueil des participants/Registration A-1600 9:00 - 9:10 Ouverture de la journée/Greetings, Sylvain G. Cloutier (Doyen de la recherche/Dean of Research, École de technologie supérieure) A-1600

9:10 - 10:00 Mot de bienvenue/Introduction, Theo van de Ven & Armand Soldera A-1600 10:00 - 10:20 Claude Pinel (FRQNT) A-1600 10:20 - 10:40 Pause-café /Coffee break Hall/Lobby

Perspectives des axes/Perspective sessions 10:40 - 10:50 Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures Dima Perepichka A-1600 10:50 - 11:00 Polymères/Polymers Mario Leclerc A-1600 11:00 - 11:10 Biointerfaces Jean-François Masson A-1600 11:10 - 11:20 Nanoscience & nanotechnologies Jean-François Morin A-1600 11:20 - 11:30 Énergie/Energy Daniel Bélanger A-1600 11:30 - 11:40 Biomédical/Biomedical John Capobianco A-1600 11:40 - 11:50 Environnement et développement/Environment and sustainable development durable Saïd Elkoun A-1600 11:50 - 12:00 Matériaux intelligents/Smart materials Fiorenzo Vetrone A-1600

Midi/Noon 12:00 - 13:00 Dîner - boîte à lunch/Box lunch Hall/Lobby

Sessions thématiques parallèles/Parallel thematic sessions Session 1 : Biomédical&Biointerfaces/Biomedical&Biointerfaces (John Capobianco)

13:00 - 13:15 Hendra Hermawan, Université Laval (Biomédical/Biomedical) A-1160 13:15 - 13:30 Estelle Juère, Freddy Kleitz, Université Laval (Biomédical/Biomedical) A-1160 13:30 - 13:45 Michèle Auger, Université Laval (Biomédical/Biomedical) A-1160 13:45 - 14:00 Tomer Noyhouzer, Janine Mauzeroll, McGill University (Biomédical/Biomedical) A-1160 14:00 - 14:15 Corinne Hoesli, McGill University (Biomédical/Biomedical) A-1160 14:15 - 14:30 Julian Zhu, Université de Montréal (Biomédical/Biomedical) A-1160 14:30 - 15:00 Pause-café /Coffee break Hall/Lobby 15:00 - 15:15 Françoise Winnik, Université de Montréal (Biointerfaces/Biointerfaces) A-1160 15:15 - 15:30 Gonzalo Cosa, McGill University (Biointerfaces/Biointerfaces) A-1160 15:30 - 15:45 Michel Grandbois, Université de Sherbrooke (Biointerfaces/Biointerfaces) A-1160 15:45 - 16:00 Jean-François Masson, Université de Montréal (Biointerfaces/Biointerfaces) A-1160 16:00 - 16:15 Christine DeWolf, Concordia University (Biointerfaces/Biointerfaces) A-1160

Session 2 : Énergie&Environnement et développement durable/Energy&Environment and sustainable development (Daniel Bélanger) 13:00 - 13:15 Dongling Ma, INRS-EMT (Énergie/Energy) A-1600 13:15 - 13:30 Nadi Braidy, Université de Sherbrooke (Énergie/Energy) A-1600 13:30 - 13:45 Mohamed Mohamedi, INRS-EMT (Énergie/Energy) A-1600 13:45 - 14:00 Jacques Huot, Université du Québec à Trois-Rivières (Énergie/Energy) A-1600 14:00 - 14:15 Shuhui Sun, INRS-EMT (Énergie/Energy) A-1600 14:15 - 14:30 Pierre D. Harvey, Université de Sherbrooke (Énergie/Energy) A-1600 14:30 - 15:00 Pause-café /Coffee break A-1600 15:00 - 15:15 Federico Rosei, INRS-EMT (Énergie/Energy) A-1600 15:15 - 15:30 Zeina Jendi, Alejandro Rey, McGill University (Environnement/développement durable/Environment/sustainable development) A-1600 15:30 - 15:45 Simon Giret, Freddy Kleitz, Université Laval (Environnement/développement durable/Environment/sustainable development) A-1600 15:45 - 16:00 Claudiane Ouellet-Plamondon, École de technologie supérieure (Environnement/développement durable/Environment/sustainable development) A-1600 16:00 - 16:15 François Brouillette, Université du Québec à Trois-Rivières (Environnement/développement durable/Environment/sustainable development) A-1600

Événements spéciaux en parallèle/Parallel special events

16:20 - 17:20 Table de discussion regroupant les quatre thématiques de recherche appliqué /Round table discussion for the four applications themes (John Capobianco, Daniel Bélanger, Saïd Elkoun, Jean-François Masson)

A1600/A1170 A1160/A1150

16:20 - 17:20 Création du comité étudiant afin de donner un plus-value à la formation étudiante/Student Meeting to provide added value for student training Soirée/Evening

17:30 - 20:30 Session d'affiches scientifiques - formule cocktail dînatoire avec service et bar/Poster session and reception Hall/Lobby

Mercredi, 4 mai 2016/Wednesday, May 4, 2016 Sessions thématiques parallèles/Parallel thematic sessions

Session 3 : Structures supramoléculaires et auto-assemblées&Polymères/Supramolecular and self-assembled structures&Polymers (Dima Perepichka) 9:00 - 9:15 Hanadi Sleiman, McGill University (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160 9:15 - 9:30 Dima Perepichka, McGill University (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160 9:30 - 9:45 Yves Dory, Université de Sherbrooke (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160

9:45 - 10:00 Federico Rosei, INRS-EMT (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160 10:00 - 10:15 Antonella Badia, Université de Montréal (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160 10:15 - 10:30 Pierre Baillargeon, Cégep de Sherbrooke (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160 10:30 - 11:00 Pause-café /Coffee break Hall/Lobby 11:00 - 11:15 Michel Lafleur, Université de Montréal (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160 11:15 - 11:30 Michèle Auger, Université Laval (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160 11:30 - 11:45 Pierre D. Harvey, Université de Sherbrooke (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160 11:45 - 12:00 Armand Soldera, Université de Sherbrooke (Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures) A-1160

Session 4 : Nanoscience et nanotechnologies&Matériaux intelligents/Nanoscience and nanotechnologies&Smart materials (Jean-François Morin) 9:00 - 9:15 Jonathan Vermette, Université de Sherbrooke (Nanosciences & nanotechnologies) A-1600 9:15 - 9:30 Suzanne Giasson, Université de Montréal (Nanosciences & nanotechnologies) A-1600

9:30 - 9:45 Anna Ritcey, Université Laval (Nanosciences & nanotechnologies) A-1600 9:45 - 10:00 Nathalie Tufenkji, McGill University (Nanosciences & nanotechnologies) A-1600

10:00 - 10:15 Elodie Boisselier, Université Laval (Nanosciences & nanotechnologies) A-1600 10:15 - 10:30 Derek Gray, McGill University (Nanosciences & nanotechnologies) A-1600 10:30 - 11:00 Pause-café/Coffee break Hall/Lobby 11:00 - 11:15 Linda Reven, McGill University (Nanosciences & nanotechnologies) A-1600 11:15 - 11:30 Fiorenzo Vetrone, INRS-EMT (Nanosciences & nanotechnologies) A-1600 11:30 - 11:45 Dongling Ma, INRS-EMT (Nanosciences & nanotechnologies) A-1600 11:45 - 12:00 Shuhui Sun, INRS-EMT (Nanosciences & nanotechnologies) A-1600

Midi/Noon 12:00 - 13:00 Lunch Hall/Lobby

Sessions thématiques parallèles/Parallel thematic sessions Session 3 : Structures supramoléculaires et auto-assemblées&Polymères (suite)/Supramolecular and self-assembled structures&Polymers (continued)

13:00 - 13:15 Jérôme Claverie, Université du Québec à Montréal (Polymères/Polymers) A-1160 13:15 - 13:30 Milan Maric, McGill University (Polymères/Polymers) A-1160 13:30 - 13:45 Tien Nguyen-Dung, Robert E. Prud'homme, Université de Montréal (Polymères/Polymers) A-1160 13:45 - 14:00 John Oh, Concordia University (Polymères/Polymers) A-1160 14:00 - 14:15 Denis Rodrigue, Université Laval (Polymères/Polymers) A-1160 14:15 - 14:30 Julian Zhu, Université de Montréal (Polymères/Polymers) A-1160 14:30 - 15:00 Pause-café /Coffee break Hall/Lobby

Session 4 : Nanoscience et nanotechnologies&Matériaux intelligents (suite)/Nanoscience and nanotechnologies&Smart materials (continued) 13:00 - 13:15 Theo van de Ven, McGill University (Matériaux intelligents/Smart materials) A-1600 13:15 - 13:30 Amélie Auge, Yue Zhao, Université de Sherbrooke (Matériaux intelligents/Smart materials) A-1600 13:30 - 13:45 Christopher Barrett, McGill University (Matériaux intelligents/Smart materials) A-1600 13:45 - 14:00 14:00 - 14:15 14:15 - 14:30 14:30 - 15:00 Pause-café/Coffee break Hall/Lobby

Événements spéciaux en parallèle/Parallel special events

15:00 - 16:00 Table de discussion regroupant les quatre thématiques de recherche fondamentaux/Round table discussion for the four fundamental themes (Dima Perepichka, Jean-François Morin, Fiorenzo Vetrone, Julian Zhu)

A1600/A1170 A1160/A1150

15:00 - 16:00 Création du comité étudiant - deuxième partie (au besoin)/Student Meeting - second part (if necessary)

15:00 - 16:00 Table de discussion regroupant les comités (programme académique, bourses, relations avec l'industrie, colloques, étudiants) /Round table discussion for working committees (academic program, scholarship, industry relations, colloquia, students)

A1600/A1170 A1160/A1150

Conclusion du colloque annuel/Annual meeting conclusion Mot de clôture du colloque/Closing remarks

Conférences/Lectures

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Présentations orales/Talks Biomédical/Biomedical

Using Metals that Corrode for Biomedical Devices Hendra Hermawan, Université Laval Biodegradable metals are metals that are expected to corrode gradually in vivo, with an appropriate host response elicited by released corrosion products, then dissolve completely upon fulfilling the mission to assist with tissue healing with no implant residues. They constitute a novel class of bioactive biomaterials which supports the healing process of temporary clinical problems. Three classes of metals have been explored: magnesium-, zinc- and iron-based alloys. Three targeted applications are envisaged: orthopaedic, cardiovascular and pediatric implants. Three levels of investigations have been conducted: in vitro, in vivo and clinical trials. Three standardization bodies have been drafting standards: ISO, DIN and ASTM. Three companies have launched their biodegradable metal-based medical products into the market. The use of biodegradable medical devices may find its suitability for enhancing the clinical outcomes and lowering the overall cost of implant surgical procedures. This presentation introduces the state-of-the-art of biodegradable metals and related research activities conducted by the presenter.

Mesoporous Silica Nanoparticles as Drug Delivery Nanovehicles Estelle Juère, Université Laval (Freddy Kleitz) Biomedical applications and more specifically drug delivery are part of our research activities. Deliver therapeutic agent to a specific location through its encapsulation into smart nanomaterials has emerged as a promising way to cure many diseases like diabetes, inflammation or cancer. Besides their biocompatibility, porous silica nanoparticles have numerous advantages as drug delivery platforms. For example, the high surface area allows for the incorporation of a high quantity of molecules and the functionalization of the external surface of the particles offers multiple pathways to tune their aqueous dispersion and more importantly, their response to external stimuli such as the pH of the media. We aim to design mesoporous silica nanospheres with defined particle diameter, pore size and structure that would carry sufficient loading of drugs or proteins to the targeted organs through oral or intravenous administrations.

Structure et orientation de fibres de soie d'araignée : Étude par microspectroscopie Raman et spectroscopie RMN Michèle Auger, Université Laval La soie d'araignée est un biomatériau protéique semicristallin qui fascine les chercheurs. En particulier, la soie qui sert de fil de survie possède des propriétés mécaniques exceptionnelles et constitue ainsi une fibre très prisée qu'il serait très intéressant de produire industriellement. Cependant, l'obtention de grandes quantités de soie naturelle n'est pas possible car les araignées sont territoriales et cannibales, donc difficiles à élever en captivité. Ainsi, la recherche actuelle est axée sur la création de soie artificielle possédant des propriétés mécaniques comparables, voire supérieures, à celles de la soie naturelle pour de potentielles applications industrielles ou médicales. Afin de pouvoir développer un biomatériau qui mime les caractéristiques de la soie, il est impératif de mieux comprendre les relations structure-propriété. Un trait unique au fil de survie est qu'il subit un rétrécissement longitudinal en présence d'eau (immersion dans l'eau liquide ou présence d'une atmosphère saturée en vapeur d'eau) qui peut atteindre 50% de la longueur initiale. Ce phénomène se nomme supercontraction. Nous nous intéressons à quantifier le changement de conformation, d'orientation et de mobilité des chaînes polypeptidiques du fil de survie induit par la supercontraction. Pour mener à bien ce projet, nous utilisons


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deux techniques complémentaires et qui ont démontré leur efficacité pour l'étude de la soie, soit la microspectroscopie Raman et la résonance magnétique nucléaire. De plus, notre groupe s'intéresse à l'étude de fibres provenant de différentes espèces d'araignée et à l'étude de protéines de soie recombinante en solution.

Redox Triggered Drug Delivery System Tomer Noyhouzer, McGill University (Janine Mauzeroll) Drug delivery systems are one of the biggest challenges and emerging fields in the world nowadays. There is a wide interest in developing an efficient method that will be able to transport a biologically active material to a desired location, and then releasing it using a simple process. This challenge is not a pure scientific challenge but is of great concern to the majority of the population. From the different approaches that tried to overcome the different developing challenges only four nanoparticle-based drug delivery platforms were approved by the FDA. We present here a novel design of a smart drug delivery liposomes based on the use of redox active phospholipids. The redox triggering is very sensitive to small and local changes; therefore, it can be applied without affecting other species in the environment as opposed to pH, temperature, ultrasound and photochemistry changes. The system was characterized using advanced methods such as SECM, TEM, DLS, flow cytometry and immunoarray fluorescent imaging. Furthermore, when loading the vesicles with anti-cancer medicine and exposing them to live cell we show that the redox induced payload mechanism is fully functional making it a promising candidate for a fully functional drug delivery system

Biomaterials for Stem Cell Bioprocessing Corinne Hoesli, McGill University The Stem Cell Bioprocessing Laboratory at McGill University is developing novel scalable methods to culture stem cell-derived products in contact with biomaterials. The main applications of this research are the production of therapeutic cells and the design of devices for cell transplantation in the fields of diabetes and cardiovascular disease. Ongoing projects in the laboratory include the engineering of biomimetic vascular scaffolds and the encapsulation of pancreatic cells in hydrogels. The long-term goal of this research is to engineer a vascularised bioartificial pancreas.

Polymers made of natural compounds Julian Zhu, Université de Montréal In the effort to improve the biocompatibility of polymeric biomaterials, natural compounds such as bile acids in the body are used in the preparation of new polymers, including dental resins, gels and degradable polymers.


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Biointerfaces/Biointerfaces

Polymers and biology: a constructive partnership Françoise Winnik, Université de Montréal Amphiphilic polymers of defined composition and architecture often interact specifically with proteins or cells and act as tools in biology. This concept will be illustrated by examples taken from current projects, such as the stabilisation of therapeutic proteins, the promotion of cell aggregation on films of phosphorylcholine-modified chitosans, and the use of polymeric nanoparticles to glue together non-cohesive cells.

Conjugated polyelectrolytes and lipid membranes: from polymer morphology and exciton transport to membrane dynamics Gonzalo Cosa, McGill University The interaction of conjugated polyelectrolytes (CPEs) with different detergents and lipids in micelles and bilayers has led to a better understanding of the structural-optical property relationships of CPEs. In turn, a range of applications have been recently reported that exploit the interaction of conjugated polyelectrolytes with lipids including the fabrication of sensing devices, the formulation of biocidal agents, and the optimization of power generation in microbial fuel cells. In particular, several sensing applications exploit changes in the photophysical and photochemical properties of CPEs imparted by their deaggregation upon membrane insertion. The changes resulting from the insertion of CPEs within membranes include spectral shifts (aggregate to monomer emission), emission enhancement, and poor exciton transport. Our group has conducted both ensemble and single molecule fluorescence studies on the role that lipid membranes play in modulating the photophysical properties of a negatively charged polyphenylene vinylene polyanion and a polyphenylene ethynylene polyanion. In this presentation we will discuss how these conjugated polyelectrolytes offer the opportunity to study membrane dynamics including membrane fusion and membrane deformation in contact with a polyelectrolyte scaffolding.

Label-free visualization and quantification of cell signalling using evanescent field sensors Michel Grandbois, Université de Sherbrooke Evanescent-field techniques such as surface plasmon resonance (SPR) and metal clad waveguide (MCWG) was recently demonstrated by our group and others as a powerful label-free approaches for real-time monitoring of cell signalling activity induced by hormones, drugs, toxins or inducers of apoptosis. In these cell biosensing applications, live cells are cultured on a metallic surface or metal clad waveguide, so their basal portion lie within the surface evanescent field. Receptors present at the cell membrane recognize biomolecules in the media , triggering intracellular signalling cascades responsible for the reorganization of the intracellular molecular content. These events are associated with refractive index change which are easily quantified through a reflectance signal. Our most recent developments in the field will be presented with a focus on SPR imaging and surface plasmon-enhanced fluorescence applied to the investigation of intracellular signalling responses of individual cells.

Surface chemistries for nanobiosensing - Chimie de surface pour les nanobiocapteurs Jean-François Masson, Université de Montréal This presentation will overview our efforts in the design of surface chemistries for the immobilization of biomolecules on gold surfaces of plasmonic sensors. Peptide monolayers and ionic liquid monolayers will be discussed for immobilizing antibodies, proteins, enzymes and other biomolecular receptors for the detection of drugs, proteins and antibodies. The biocompatibility with crude biofluids will be discussed. Cette présentation portera sur nos efforts pour créer des chimies de surface pour l'immobilisation de biomolécules sur les surfaces d'or de biocapteurs plasmoniques. Les surfaces de peptides et de liquides


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ioniques seront discutées dans le cadre de l'immobilisation de protéines, d'anticorps et d'enzymes pour la détection de médicaments, d'anticorps et de protéines. La biocompatibilité de ces surfaces avec les fluides biologiques sera également discutée.

Langmuir monolayers - from model biomembranes to functional thin films Christine DeWolf, Concordia University Langmuir monolayers at the air-water interface are commonly used as models of biological membranes, as a means to pre-organize materials for thin films and to understand self-assembly processes at interfaces. Our research focuses on the impact of composition and molecular structure on film organization, morphology and rheology. The impact of these properties on biologically relevant processes and the design of functional films will be presented.


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Énergie/Energy

Multifunctional materials for energy conversion and storage Federico Rosei, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications We describe structure/property relationships in multifunctional materials, specifically multiferroic thin films and nanostructures used for solar energy conversion and photoelectrochemical water splitting.

Towards harvesting more solar photons by developing nanostructured materials and assemblies Dongling Ma, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications Efficiently harvesting visible and near infrared (NIR) photons represents an attractive approach to improve the efficiency of solar-to-electricity conversion, solar-to-fuel conversion and photocatalysis. Plasmonic nanostructures with unique surface plasmon resonance have recently been explored for enhancing solar energy harvesting in the visible and NIR regimes. On the other hand, NIR quantum dots (QDs) with size tunable bandgaps and high potential for multiple exciton generation represent a class of promising materials for new generations of solar cells. In this talk, I will present our recent work on the synthesis of plasmonic nanostructures, NIR QDs, and related assemblies as well as their applications in solar cells, solar fuel and photocatalysis.

Crystalline and microstructural investigation of nanomaterials for catalysis Nadi Braidy, Université de Sherbrooke The performance of a catalytic process depends largely on several intrinsic parameters of the catalysts: chemical nature, crystalline phase, size and shape. The efficient design of a novel catalyst needs to take into account not only these parameters but their change in operation. Here, we probe the materials side of the interface at several steps of the process: following synthesis of a catalyst, during its activation phase, its operation and deactivation. We will focus on spinel-based catalyst investigated using in situ diffraction (XRD) and spectroscopy (EXAFS) techniques. Emphasis will also be placed on the nanostructures of the catalyst before and after operation using advanced transmission electron microscopy techniques.

Concepts and Nanostructures for Micro Energy Systems Mohamed Mohamedi, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications Micro-energy sources are scientific and technological barriers that must be overcome in Quebec. By micro-energy source "micro-electrochemical energy source", we are interested in researching and developing new generation of micro fuel cells. Micro or miniature fuel cells "A global competition, opportunities for Quebec" are among the most promising avenues that could revolutionize power sources for portable electronics (phones, laptop,...), external and implantable medical devices for the treatment of human illness pacemakers, sensors,..). It remains, however, that the power density delivered by micro fuel cells known to date are not yet sufficient for the targeted applications. The first reason is that the development of such systems relied only on MEMS (Micro-Electro-Mechanical Systems) technology. The second reason is that conventional fabrication techniques of catalyst layers for macro fuel cells are practically non-feasible in microchannels constituting the miniature cells. Thus, the future of miniature fuel cells technologies is strictly dependent on new concepts of catalyst layers, innovative structures and synthesis routes that allow tailor-designing and engineering of catalyst layers and their integration into microfluidic channels in a precise manner. Our aim is to create a synergy between the MEMS and nanotechnology to develop these systems. In this talk, we will discuss the concept and our progress in the development of binderless on macro-substrates, which will take us in the future to address other scientific and technological challenges that is the integration of such free-standing catalyst layers in very confined spaces such as pre-patterned microchannels, the heart of miniature fuel cell systems.


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Development of materials for hydrogen technologies Jacques Huot, Université du Québec à Trois-Rivières In this presentation I will show my current and future fields of researches. Presently, we are working on cost reduction of 'conventional' metal hydrides for hydrogen storage. This cost reduction could be achieved by using industrial grades of materials; prepare the alloy by mechanical deformation; change of composition; addition of a catalyst. I am also investigation the effect of hydrogen on the tribological properties of materials. Future field of research is hydrogen embrittlement, diffusion, and metal hydrides as battery materials.

Nanomaterials for Energy Conversion and Storage in Fuel Cells and Batteries Shuhui Sun, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications The Sustainable Nanotechnology (SUN) Laboratory at INRS-EMT is developing functional nanomaterials (Graphene, CNTs, metal and metal oxide nanostructures, and nanocomposites) for Sustainable Energy and Environmental applications, including Fuel Cells, Lithium and Sodium Batteries, Supercapacitors, and Wastewater treatment. In this talk, I will introduce our recent work on highly efficient low-Pt (nanowires, nanotubes, and single atoms) and Pt-free (e.g., Fe/N/C) catalysts for fuel cells, and graphene based nanocomposites for batteries.

Photonique ultra-rapide dans les solides et modèles solubles Pierre D. Harvey, Université de Sherbrooke Cette présentation focalise sur les matériaux polymériques conjugués organiques et organométalliques avec applications potentielles dans le domaine des cellules solaires. L'objectif à long terme est d'établir une relation structure-propriétés avec les rendements des cellules et les vitesses des différents processus de transfert d'énergie, de migration de l'énergie d'excitation et de transfert d'électron dans l'état solide.


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Environnement/développement durable/Environment/sustainable development

Gas Hydrates: Thermophysical Properties via Ab Initio Simulations Zeina Jendi, McGill University (Alejandro Rey) Key thermophysical properties of methane hydrate were determined using ab initio modelling. Using density functional theory, the second-order elastic constants, heat capacity, compressibility, and thermal expansion coefficient were calculated. A wide and relevant range of pressure-temperature conditions were considered, and the structures were assessed for stability using the mean square displacement and radial distribution functions. Methane hydrate was found to be elastically isotropic with a linear dependence of bulk modulus on pressure. Equally significant, multi-body interactions were found to be important in hydrates, and water-water interactions appear to strongly influence compressibility like in ice Ih. While the heat capacity of hydrate was found higher than that of ice, the thermal expansion coefficient was significantly lower, most likely due to the lower rigidity of hydrates. The mean square displacement gave important insight on stability , heat capacity, and elastic moduli, and the radial distribution functions further confirmed stability. The presented results provide a much needed atomistic thermoelastic characterization of methane hydrates and are essential input for the large-scale applications of hydrate detection and production.

Functionalized mesoporous solid phase for Rare Earth Elements separation / Phase solide mesoporeuse fonctionnalisé pour la séparation de Terres Rares Simon Giret, Université Laval (Freddy Kleitz) Les Terres Rares sont des éléments stratégiques qui rentrent dans la conception d'un très grand nombre de technologies modernes. Actuellement l'extraction liquide-liquide est utilisée pour leurs productions à partir de minerais, ce procédé est excessivement polluant et long car il nécessite de multiples cycles pour obtenir les éléments purs. Afin de s'affranchir de ces contraints, notre équipe travail à la conception de phases solides mesoporeuses fonctionnalisées pour réaliser des extractions solide-liquide. En fonction de la nature du support solide (Silice, Carbone), du type de porosité (mesoporeuses 2D ou 3D, tailles des pores, hiérarchique dans des monolithes,...) et de la nature de la fonctionnalisation de surface (différents types de ligands peuvent être utilisés pour complexer les Terres Rares en surface du support) il est possible d'obtenir des phases solides sélectives pour séparer les Terres Rares de leur milieu et également les une des autres avec des propriétés d'extractions prometteuses (cinétique, capacité, réutilisabilité).

Hybride d'oxyde de graphène à partir du sucre et d'argile Claudiane Ouellet-Plamondon, École de téchnologie supérieure La carte de route technologique du graphène montre une diversité d'applications en santé, environnement, production, électronique, photonique, senseurs, stockage et génération d'énergie, composites et biomédicales. Les argiles sont accessibles et améliorent la mécanique, rhéologie et la résistance au feu des polymères, nanomatériaux et composites. Dans une perspective de développement durable, la synthèse d'un hybride d'oxyde de graphène et argile à partir du sucre devient prometteuse. L'hybride oxyde de graphène-argile a été caractérisé par spectroscopie FTIR, Raman et diélectrique, ainsi que par la surface spécifique. La mesure de la conductivité en fonction de la pression montre que cet hybride a une conductivité qui s'approche de certain graphène commercialement disponible et qu'elle est supérieure à celle de l'argile. Les prochaines étapes sont de fabriquer des composites pour préciser les applications.


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Les fibres cellulosiques phosphorylées : le point de départ de nouveaux matériaux multifonctionnels biosourcés François Brouillette, Université du Québec à Trois-Rivières La fibre cellulosique est un produit naturel abondant avec une bonne capacité d'isolation thermique et acoustique. Toutefois, il est loin d'être considéré comme la référence en isolation dans l'industrie de la construction à cause de son caractère hygroscopique et inflammable. L'humidité entraïne d'un part l'entassement de la couche avec une perte de pouvoir isolant, et d'autre part favorise l'inoculation et la propagation des microorganismes avec l'apparition de moisissure sur le substrat cellulosique. Deux réactions chimiques enchaïnées permettent d'éliminer ces inconvénients. Tout d'abord, la surface de la fibre est phosphorylée avec un ester de phosphate en présence d'urée fondue. Les groupements phosphates greffés rendent la cellulose ignifuge et l'activent pour une deuxième réaction qui est l'alkylation. Les chaïnes aliphatiques sont liées aux phosphates à l'aide d'un groupe partant comme le tosylate. L'alkylation est assez efficace pour rendre les fibres hydrophobes mais elle n'arrive pas à les plastifier. La fibre Kraft phosphorylée et alkylée garde sa morphologie initiale tout en lui ajoutant un caractère à la fois ignifuge et hydrophobe.


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Structures supramoléculaires et auto-assemblées/Supramolecular and self-assembled structures

Molecular Lego with DNA: Building and Printing Structures for Materials Science and Nanomedicine Hanadi Sleiman, McGill University DNA is known to us as the molecule of life, the blueprint that defines who we are. But the very properties that make DNA such a reliable molecule for information storage also make it one of the most remarkable building materials. Over the past few years, our research group has taken DNA out of its biological context, and has used this molecule to build 2D- and 3D-structures that are stimuli-responsive. We will report a molecular printing strategy, which chemically transfers a specific pattern of DNA strands from a DNA nanostructure to other materials, such as gold nanoparticles and synthetic polymers. We show that the materials inherit the information encoded in the parent template with high-fidelity. We will also describe a simple and high yield synthesis of monodisperse and fully sequence-controlled polymers, their self-assembly properties, and their attachment to DNA. The applications of these DNA structures as selective drug delivery vehicles to cancer cells will be described.

Towards Supramolecular Design of Organic Semiconductors Dima Perepichka, McGill University The idea of rational design of electronic properties of materials via manipulation of a molecular structure is a centerpiece of organic electronics. Indeed, a range of organic materials with metallic, semi- and superconducting, magnetic, non-linear optical and lasing properties have been reported. However, an optimization of these properties and realization of high-performance organic optoelectronic devices is still largely an empirical exercise. The 'rational design' approach is severely limited by our inability to control a supramolecular structure and resulting 'solid state' properties, which emerges as a fundamental challenge of the field. Our recent work on controlling the supramolecular structure using H-bonding and other weak interactions, and correlating this structure to charge transport properties, will be the subject of this presentation.

Nanotubes and Nanospheres from E and Z Lactams Yves Dory, Université de Sherbrooke The design and synthesis of cyclopeptides self-assembling as supramolecular tubes and spheres will be described. These objects can be used as scaffolds to control the stacking of various molecules like TTFs, azobenzenes, alkynes and other polymerizable units.

Exploring Molecular Self-Assembly At Surfaces Federico Rosei, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications The adsorption and self-assembly of organic molecules at surfaces has recently been investigated extensively, both because of the fundamental interest and for prospective applications in nanoelectronics. Molecule-molecule and molecule-substrate interactions can be tuned by appropriate choice of substrate material and symmetry. Upon molecular adsorption, surfaces typically do not behave as static templates, but often rearrange to accommodate different molecular species. We review recent experiments using Scanning Tunnelling Microscopy, providing new insight into fundamental properties such as molecular diffusion and self-assembly via surface templating and H-bonding driven by co-adsorption. Our approach is to modify surfaces providing suitable surface cues, that may guide the assembly of adsorbates. Recent advances in using the substrate as catalyst for surface confined polymerization reactions will also be discussed.


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Putting Surface-Confined Redox Reactions to Work Antonella Badia, Université de Montréal Due to their attractive electrochemical properties (facile electron transfer, low oxidation potential, and two stable redox states), ferrocene-terminated organic monolayer films have attracted significant interest as advanced functional coatings for biosensing and device applications. The talk will describe work focused on using the molecular reorientation and surface-confined ion-pairing reaction that accompany electron transfer in self-assembled monolayers (SAMs) of ferrocenylalkanethiolates on gold for (i) micromechanical actuation and (ii) detection of the micellization of anionic surfactants in aqueous solution.

Étude comparative de cristaux organiques isomorphes d'alcynes et d'haloalcynes Pierre Baillargeon, Cégep de Sherbrooke Nos activités de recherche visent principalement à synthétiser et à caractériser des cristaux organiques ne différant que par une fonction alcyne ou haloalcyne (Cl, Br, I). Cette similitude structurale permet d'engendrer des cristaux isomorphes, c'est-à-dire des cristaux possédant des mailles de même symétrie et dont les paramètres sont proches. Ces cristaux isomorphes constituent des systèmes de choix pour nous permettre d'améliorer notre compréhension entre la relation structure cristalline/propriétés des matériaux, en particulier dans le domaine de l'optique non linéaire.

Auto-assemblages lipidiques : fondements et applications Michel Lafleur, Université de Montréal Notre programme de recherche vise à caractériser l'organisation d'auto-assemblages biomoléculaires, à dégager les lois physico-chimiques en jeu, à identifier les relations entre la structure et les fonctions de matériaux biologiques et à en exploiter les propriétés en vue de diverses applications en biotechnologie. Nous nous intéressons plus spécifiquement aux auto-assemblages lipidiques, en utilisant de puissantes techniques de caractérisation comme la résonance magnétique nucléaire à l'état solide et la nano/microspectroscopie vibrationnelle. Notre groupe contribue de manière significative à la compréhension de la relation structure/fonction de certains matériaux biologiques comme les membranes biologiques et le stratum corneum, la couche supérieures de l'épiderme. Par exemple, nous avons montré la présence d'une proportion importante de lipides de la peau existant sous forme solide, un trait unique qui est intimement associé à la barrière cutanée. Récemment, le groupe examine les règles physico-chimiques qui dictent l'extraction lipidique de membranes et la fragmentation de celles-ci par des protéines et des peptides afin de développer une meilleure compréhension des mécanismes moléculaires de ces phénomènes impliqués dans des processus biologiques vitaux tel que le transport inverse du cholestérol et la maturation des spermatozoïdes. Finalement, notre groupe exploite les auto-assemblages lipidiques dans le but de développer la vectorisation de médicaments. Entre autres, la découverte d'une nouvelle phase lipidique, obtenue avec des mélanges binaires d'un amphiphile monoalkylé et un stérol permet la création de nouveaux nanovecteurs qui montrent des propriétés distinctes telles qu'une imperméabilité remarquable et un fort potentiel pour la libération contrôlée de médicaments; ces nanovecteurs peuvent être fabriqués, par exemple, sensibles au pH ou à la lumière.

Étude spectroscopique de la structure, de l'agrégation et des interactions membranaires de peptides synthétiques et naturels è potentiel antimicrobien et de peptides amyloïdes Michèle Auger, Université Laval La résistance des bactéries à l'égard des antibiotiques est l'un des grands enjeux actuel dans le secteur de la santé, notamment avec l'apparition de nouvelles bactéries dites multirésistantes. Ce problème de santé publique a généré un engouement vers l'étude de substances naturelles ayant une activité antimicrobienne, et ce, par l'intermédiaire de mécanismes d'action inédits. Parmi celles-ci, on retrouve les peptides


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antimicrobiens cationiques qui sont des effecteurs de la réponse immunitaire non spécifique. Nous nous intéressons à l'étude de l'interaction entre des membranes lipidiques modèles et un peptide synthétique 14-mère. En collaboration avec le groupe de recherche du professeur Normand Voyer, des résidus leucine ont été remplacés par des résidus chargés positivement à pH physiologique afin d'obtenir des peptides sélectifs envers les membranes bactériennes. D'autre part, nous étudions aussi un peptide antimicrobien naturel, la thanatine. Ce peptide naturel présent chez la punaise soldat (Podisus maculiventris) se démarque par sa structure secondaire en forme d'«épingle à cheveux» stabilisée par un pont disulfure. On connait déjà son activité contre plusieurs bactéries à Gram positif et négatif ainsi que certaines cellules fongiques. Notre groupe s'intéresse aussi à l'étude de peptides amyloïdes, en particulier un peptide de 12 acides aminés dérivé de l'alpha-synucléine, une protéine impliquée dans la maladie de Parkinson. L'étude de la structure, de l'agrégation, des interactions membranaires et du mécanisme d'action de ces différents peptides fait intervenir plusieurs techniques spectroscopiques, notamment la spectroscopie RMN des solides, la spectroscopie infrarouge, la spectroscopie de fluorescence et le dichroïsme circulaire.

Polymères de coordination 3D à base de thioéthers Pierre D. Harvey, Université de Sherbrooke Cette présentation concerne l'auto-assemblage de fragments métalliques à base de Cu(I) et de thioéthers afin de générer des polymères de coordination 3D et des MOFs, metal-organic-frameworks. Les propriétés d'adsorption de gaz et de petites molécules (solvants) ainsi que les propriétés photophysiques seront présentées. Une entrée dans la chimie des MOMFs, metal-organometallic-frameworks sera aussi discutée.

Multi-scale Simulation of Soft Matter Armand Soldera, Université de Sherbrooke The gap between understanding the structure of a molecule, the assembly of multiple molecules and the final functionality of a material is significant and is often neglected. In fact, the link between the micro- and the macro-scales is far from being straightforward. To describe applied systems, a series of models with a specific set of rules is required. Models must be chosen accurately to efficiently describe the system of interest and each scale needs a certain level of approximation in order to address a specific problem. To ascertain accuracy of the representation, validation with experiments is a crucial step. A better understanding of the molecular behaviors that give rise to a specific property will result. Thus, multi-scale simulation allow to increase the performance of existing materials, or even to propose new materials. Several examples coming from our lab are discussed.


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Nanosciences et nanotechnologies/Nanosciences and nanotechnologies

Étude des isomères de spin de l'eau et leur interconversion Jonathan Vermette, Université de Sherbrooke Les propriétés des isomères de spin nucléaire de la molécule H2O suscitent un grand intérêt en astrophysique pour l'information que ceux-ci peuvent apporter sur la température des corps célestes tels que les comètes et les régions de formation stellaire [1,2]. En effet, le ratio des populations des molécules d'eau magnétiques (H2O-ortho; Ms=1) et non-magnétiques (H2O-para; Ms=0) est une constante d'équilibre thermodynamique qui se rapporte à la température de spin (Tspin) de l'eau. Le faible couplage qui existe entre le moment magnétique nucléaire de la molécule et ses degrés de liberté de vibration et de rotation donne lieu à un délai dans l'atteinte de l'équilibre thermique de Tspin résultant en un effet de mémoire pouvant même remonter à des millions d'années selon certaines sources. Le travail qui sera présenté repose sur une étude expérimentale des mécanismes de conversion de spins nucléaires aujourd'hui mal connus et pouvant potentiellement infirmer l'interprétation des astrophysiciens en la matière. Le principe d'indiscernabilité des atomes d'hydrogène de H2O implique des règles de sélection rigoureuses entre les états magnétiques et rotationnels de la molécule permettant ainsi de sonder l'abondance relative des populations H2O-ortho et H2O-para via des techniques de spectroscopie rovibrationnelle et rovibronique [3]. Le premier volet de l'exposé consistera a présenter des résultats de spectroscopie infrarouge de la conversion de spin de différents isotopomères (H2O16, H2O17 et H2O18) de l'eau piégée et libre de rotation dans une matrice d'argon condensée dans un vide cryogénique. Les différents mécanismes menant à la conversion des isomères de spins nucléaires tels que les interactions intramoléculaires, l'effet de confinement ainsi que l'interaction des phonons de la matrice avec la molécule seront discutés. La seconde partie de l'exposé portera sur la conception d'un nouveau système, entièrement développé par notre équipe, qui permet de séparer H2O-ortho de H2O-para en p hase gaz par leur focalisation dans un jet moléculaire à l'aide d'une une lentille hexapolaire magnétique [4]. La détection de l'enrichissement H2O-ortho est effectuée via une technique de spectroscopie rovibronique par ionisation multi-photonique résonante (REMPI : Resonance-enhanced multiphoton ionization) qui permet l'ionisation sélective des molécules dans des états rotationnels spécifiques qui sont ensuite dirigées dans un spectromètre de masse à temps de vol. En plus de permettre l'étude de conversion des isomères de spin nucléaire de H2O en phase gaz, ce type de système ouvre la voie à des applications en RMN où H2O-ortho enrichie sur une surface étudiée jouerait le rôle d'agent de contraste.

1. Crovisier, J., et al., The spectrum of Comet Hale-Bopp (C/1995 O1) Observed with the Infrared Space Observatory at 2.9 Astronomical Units from the Sun Science 275, 1904-1907 (1997); Mumma, M.J. et al., Detection of water vapor in Halley's comet, Science 232, 1523-1528 (1986).

2. Hogerheijde, M.R, et al., Detection of the Water Reservoir in a Forming Planetary System, Science 334, 338-340 (2011). 3. Turgeon et al, Preparation, isolation, storage and spectroscopic characterization of water vapour enriched in the ortho-H2O nuclear

spin isomer, Phys.Rev.A 86, 062710 (2012). 4. Kravchuk et al, A Magnetically Focused Molecular Beam of Ortho-Water, Science 331, 319-321 (2011).

Stimuli-Responsive and Nanostructured Polymer Films for Modulating Surface Properties: Fabrications, Applications and Limitations Suzanne Giasson, Université de Montréal Structured responsive surfaces have properties and responsiveness that are contingent on the chemical composition, size and shape of structure, elasticity. A number of experimental studies have shown that polymer coatings can be efficiently used to control surface properties such as friction and adhesion between surfaces. However, they are generally suffering from major shortcomings such as lack of responsiveness selectivity and reversibility, poor environmental stability and limited understanding of the structure-function relationship, which are all critical to design reliable rules for building multifunctional surfaces. Experimental studies on different nanostructured responsive surfaces have been carried out in order to overcome the


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difficulty of systematically controlling the grafting density, surface roughness and the location of interfacial plane. Surface properties and interactions of these different nanostructured responsive surfaces (polymer brushes, 2D nanogel arrays) carried out using the Surface Forces Apparatus and similar molecular techniques will be presented in order to elucidate the responsiveness mechanism and the structure-property relationship of such smart surfaces.

Nanoparticles for applications in optics and photonics Anna Ritcey, Université Laval Our research activities focus on the development of new materials based on functional nanoparticles, including metallic, magnetic and luminescent particles. One underlying theme of our work is the organization of nanoparticles at interfaces or within polymer matrices. For example, we are investigating block copolymer monolayers as templates for the fabrication of ordered nanoparticle assemblies. In the case of metal nanoparticles, such assemblies exhibit plasmonic properties relevant to a number of sensing applications. We are also interested in the controlled synthesis of lanthanide fluoride nanoparticles within inverse micelles. These particles offer potential applications in fluorescence imaging because of the unique luminescence properties of lanthanide ions. Finally, we are employing magnetic nanoparticles for applications in adaptive optics.

Biocolloids and Surfaces Laboratory Nathalie Tufenkji, McGill University Our research focus is in the area of (bio)colloid-surface interactions with applications in protection of water resources, engineering of biosensors, antimicrobial materials, and development of safe nanotechnology. The Biocolloids and Surfaces Laboratory combines tools from surface and colloid science with techniques in molecular, cellular, and microbiology to address interdisciplinary problems that have implications for protection of the environment and public health. Some of the instruments used in our research include a quartz crystal microbalance with dissipation monitoring (QCM-D), a NanoTweezer, a scanning imaging ellipsometer, and an enhanced darkfield hyperspectral microscope. Ongoing projects include: (i) the interaction of contaminants with supported lipid bilayers, (ii) identification of natural antimicrobials, and (iii) graphene-based hydrogels for water treatment.

Les nanosciences au service de l'ophtalmologie Elodie Boisselier, Université Laval L'œil est l'organe présentant le plus grand nombre de maladies héréditaires. La malvoyance et la cécité ont un impact social et financier très important et affectent les gens, qu'ils soient vieillissants ou dans leur meilleure période de productivité économique. Au Canada, plus de 1,6 millions de personnes souffrent d'une perte de vision. Cependant, les traitements actuellement proposés en ophtalmologie doivent être optimisés par l'amélioration de leur efficacité et la réduction de leur toxicité et de leur coût. Il est donc nécessaire de concentrer la recherche sur les thérapies proposées en ophtalmologie, notamment sur l'optimisation des médicaments appliqués par voie topique, en concevant de nouveaux systèmes de relargage de médicaments. De plus, les causes d'un grand nombre de maladies oculaires sont encore inconnues ou non expliquées. La recherche fondamentale dans le domaine de la vision est donc primordiale afin de mieux comprendre l'étiologie de ces maladies oculaires et d'ainsi améliorer la qualité de vie des Canadiens et les soins qui leur sont offerts. Les travaux menés dans mon laboratoire de recherche portant sur l'utilisation de différents domaines des nanosciences adaptés en ophtalmologie seront ainsi présentés.


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Film preparation from chiral nematic suspensions of cellulose nanocrystals Derek Gray, McGill University Renewable, biodegradable nanocellulose-based materials are gaining traction for a wide variety of applications. Optical properties of films made from cellulose nanocrystals resemble those of cholesteric liquid crystals, suggesting applications as photonic materials. However, the optical properties have to date been disappointing. The processes involved in the transition from chiral nematic suspension to solid film have been re-examined, with the aim of exploiting the unique material and chiral properties of cellulose-based nanomaterials.

Assembly of Nanoparticles into Cubic Lattices in Blue Phase Liquid Crystals Linda Reven, McGill University Although nanoparticles (NP) have been used to stabilize blue phases (BPs), ordered NP assemblies in BPs have not been previously reported. Here we describe the spontaneous formation of thermally reversible, cubic crystal nanoparticle (NP) assemblies in blue phase (BP) liquid crystals as characterized by polarized optical microscopy and synchrotron small-angle X-ray scattering (SAXS). Gold NPs, with an average diameter of 4 nm, and functionalized with mesogenic ligands, were uniformly dispersed into a blue phase mixture which showed both BP I and BP II phases. Upon heating or cooling into the blue phases, sharp Bragg peaks appear, distributed in rings. In slowly annealed samples where there are fewer crystallites, the width of a single Bragg peak indicates crystallite sizes >10 µm. At higher particle concentrations, the X-ray scattering profiles become powder-like with well-defined rings. The same Bragg reflections for each phase appear independent of NP concentration or whether the sample is cooled or heated. The indexing of the Bragg peaks yield lattice parameters comparable with those of the blue phase, varying between ~ 370 to 420 nm depending on the temperature and amount of chiral dopant. At the BP I to BP II phase transition, the NP lattice reversibly switches between two different cubic structures. The gold NPs assemble into giant cubic crystals by selectively migrating to periodic strong trapping sites in the lattice of disclination lines.

Multifunctional Nanoplatforms Based on Near-Infrared Excited Nanoparticles Fiorenzo Vetrone, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications The ability to stimulate luminescent inorganic nanoparticles with near-infrared (NIR) light has made possible their use in a plethora of biological and medical applications. In fact, the biggest impact of such materials would be in the field of disease diagnostics and therapeutics, now commonly referred to as theranostics. The use of NIR light for excitation mitigates some of the drawbacks associated with high-energy light (UV or blue) excitation, for example, little to no background autofluorescence from the specimen under investigation as well as no incurred photodamage. Moreover, one of the biggest limitations is of course, that of penetration. As such, NIR light can penetrate tissues much better than high-energy light especially when these wavelengths lie within the three so-called biological windows. Thus, significant strides have been made in the synthesis of inorganic nanomaterials whose excitation as well as emission bands lie within one of these three optically transparent biological windows. Here, we present the synthesis of various NIR excited (and emitting) inorganic core/shell nanostructures and demonstrate their potential use in nanomedicine. Furthermore, we will show how such nanoparticles can be used as building blocks towards developing multifunctional nanoplatforms for simultaneous detection and therapy of disease.

Controlled synthesis of nanostructures of different morphologies and with multiple components Dongling Ma, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications Nanomaterials are finding many important applications due to their unique properties, such as superparamagnetism and size tunable optical bandgaps, both arising from the quantum confinement effect


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related to their small size. The properties of nanomaterials are also largely affected by their morphology and the way different structural units are assembled in the case of multi-component nanomaterials. The latter offers even greater flexibility in tuning their properties by exploiting synergistic effects or by combining multiple functions into a single structure. In this talk, I will briefly introduce several different types of nanostructures we developed recently, such as magnetic/catalytic core/shell bimetallic structures, non-symmetric one-dimensional plasmonic nanostructures, and semiconductor multi-shell nanostructures.

Atomic level controlled synthesis of nanomaterials by ALD Shuhui Sun, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications Atomic layer deposition (ALD) an emerging technique in designing nanomaterials with control in the atomic level, for various applications in catalysis, batteries, solar cells, environmental, and bio-nanotechnology. Downsizing catalyst nanoparticles to single atoms is highly desirable to maximize their use efficiency, however, very challenging. Here we report a practical synthesis for isolated single Pt atoms anchored to graphene and N-doped graphene nanosheet using the atomic layer deposition (ALD) technique. HRTEM and EELS spectroscopy were employed to identify the single atoms. The novel catalyst exhibit significantly improved catalytic activity (up to 10 times) over that of the state-of-the-art commercial Pt/C catalyst. This work is anticipated to form the basis for the exploration of a next generation of highly efficient single-atom catalysts for various applications.


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Polymères/Polymers

From commodity polymer to functional materials Jérôme Claverie, Université du Québec à Montréal Nous avons transformé des polymères très simples obtenus par des voies de polymérisation catalytique respectueuses de l'environnement en des macromolécules fonctionnelles. Par exemple, le polyéthylène a été transformé en un polymère thermoreversible qui peut changer de forme sous l'effet d'un stimulus chimique. Nous nous sommes intéressés à la chimie du polynorbornène et avons récemment démontré que ces polymères pouvaient être utilisés développer de nouveaux thermodurcissables dépourvus de bisphénol. Nous avons également démontré la capacité de ces polymères à stabiliser très efficacement les nanotubes de carbone de manière non covalente. De plus ces polymères peuvent être électrofilés avec ou sans nanotubes de carbone conduisant à la formation de fibres micrométriques. En combinant toutes ces propriétés uniques, des thermodurcissables bisourcés jusqu'à 70% ont été obtenus sous forme de pièces, de fibres et de films transparents conducteurs (>10,0 00S/m).

Self-Assembly of Gradient Copolymers Milan Maric, McGill University Poly(methyl methacrylate)-grad-poly(styrene) copolymers were synthesized by nitroxide mediated polymerization (NMP) for application towards next-generation lithographic materials. Such gradient copolymers are compared against block copolymers in terms of self-assembly performance. Using a polymer brush to align the domains vertically, Their self-assembly performance was assessed relative to block copolymers with identical molecular properties and found to have similar feature sizes. However, with increasing gradient length, the self-assembly is negatively affected, producing films with very little order and much higher defect densities than block copolymers or polymers with short gradient lengths.

Crystallization of stereocomplexes of PLLA/PDLA in ultrathin films with and without block copolymers Tien Nguyen-Dung, Université de Montréal (Robert E. Prud'homme) Polylactides exist in two different enantiomeric forms: poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA); both are semicrystalline polymers. During crystallization in ultrathin films, polylactides give edge-on lamellae that crystallize with a curvature having an 'S' shape with PLLA and a 'Z' shape with PDLA. In the case of stereocomplexes formed by the mixture of PLLA and PDLA, equimolar blends give hexagonal single crystals while non-equimolar blends show triangular single crystals. Moreover, the crystallization in ultrathin films of PDLA with poly(l-lactide-b-2-dimethylaminoethyl methacrylate) linear AB diblock copolymers and BAB triblock copolymers with PLLA as the central block leads to unique morphologies.

Design of multifunctional (block) copolymers and their hybrid materials John Oh, Concordia University Our research brings together scientific exploration in the areas of polymer chemistry at the interface of biology and nanoscience. We primarily focus on the design and development of macromolecular nanoscale devices as multifunctional drug delivery nanocarriers and cellular imaging platforms for biological and biomedical applications. Our particular interests are the design and synthesis of multifunctional polymers to fabricate their hybrid nanomaterials. We have explored multidentate block copolymer (MDBC) strategy to stabilize superparamagnetic iron oxide nanoparticles (SNPs) as an effective T1-positive MRI contrast agent with excellent colloidal stability in various pH and physiological conditions. Currently, we explore this strategy in several aspects; including in situ synthesis of MDBC/SNPs in aqueous solution as well as development of MSBC/QDs hybrids for optical imaging. Recently, we have developed novel reduction-


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responsive sheddable carbon nanotubes dispersed in aqueous solution for fuel cell applications. The polymer are hydrophilic (rendering stable aqueous dispersion), functionalized with pendant pyrene groups (capable of adhesion to carbon surfaces through π-π non-covalent interactions), and labeled with disulfide linkages (exhibiting reduction-responsive cleavage). After metal-based nanoparticles have been uniformly deposited on the carbon materials, the long polymer chains will be shed from the carbon surfaces, thus retaining a clean surface for electrochemical catalytic reactions.

Polymères microporeux pour des applications en séparation des gaz Denis Rodrigue, Université Laval Pour la séparation des gaz, les membranes polymères ont connu des développements importants dans les dernières années. Dans notre groupe, on s'intéresse à insérer une microporosité afin de contrôler la perméabilité et des nanoparticules afin de contrôler la sélectivité. Dans cette présentation, différentes méthodes de fabrication seront présentées afin de produire des membranes pour une série de gaz incluant: hydrogène, méthane, dioxyde de carbone, azote et oxygène.

Shape-memory polymers and self-healing gels Julian Zhu, Université de Montréal We have designed and prepared new synthetic polymers with multiple-shape memory effects and self-healing properties as hydrogels through the formation of inclusion complexes. Such materials may have potential in biomedical applications.

Affichages/Poster presentations

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Matériaux intelligents/Smart materials

A novel aqueous process for the production of functional textile from cellulose fibers Theo van de Ven, McGill University We have developed an environmentally-friendly process to produce textile fibers from cellulosic material using a carboxylmethylation reaction. Trials on a pilot spinneret showed that textile fibers can be produced at industrial speeds and drawing rates. The resulting fibers have a degree of substitution ranging from 0.1 - 0.4 which greatly improves the hydrophilic behavior of the produced textile. As a result, the water absorbency of this textile is high, which limits its use to one-time applications. To extend the range of applications, the fibers can be post-treated by modifying the functional carboxyl groups into hydrophobic groups. We also focus on conditions that affect the hydrophobicity of our yarn in order to obtain absorption properties similar to those of cotton fabric which has a water uptake of about 1.5 g/g yarn.

Advanced Stimuli-Responsive Polymers and Hybrid Materials Amélie Auge, Université de Sherbrooke (Yue Zhao) In recent years our main research interest has been focused on the design, synthesis and study of polymers or polymer/inorganic nanoparticle hybrid materials that can react to a variety of stimuli such as change in pH or temperature and exposure to light or ultrasound or carbon dioxide. We try to develop new methods or materials design to address some challenging issues (e.g., controllability, predictability, effect amplification) that may help exploiting those polymers for applications. Examples of our ongoing research include near-infrared light-sensitive polymer hydrogels, ultrasound- or light-controllable shape-memory and healable polymers, and CO2-switchable polymers.

Walk and Roll: New Azo Photo-Actuators for Little Light-Powered Robotics Christopher Barrett, McGill University Materials based on azobenzene are mimics of the retinal photo-switch that enables vision, responding physically and mechanically to permit solar energy to be converted directly to mechanical work. Irradiation with light in the solar spectrum at sun-like intensities will be shown to lead to a measurable reversible photo-expansion of these coatings, of up to a few %, allowing the materials to function as photo-mechanical switches or light energy harvesters and actuator devices. New azo materials and polymers to optimize this effect will be presented, and some simple macroscopic devices will be demonstrated that take mechanical advantage of this effect for larger scale motion driven by sunlight. The mechanism for this effect will be discussed from studies using ellipsometry, light-bending of AFM cantilevers, high-pressure Raman spectroscopy, and neutron reflectometry. Some simple proof-of-principle functioning devices will be presented, that convert sunlight directly into mechanical motion for materials that bend and wiggle, crawl, walk and roll.


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Affichages/Poster presentations 1. Smart magneto-responsive hydrogels triggered by low frequency rotating magnetic fields for

controlled release applications Shahab Boroun, Université Laval (Faical Larachi) Design and fabrication of polyelectrolytes with tunable transport properties by external stimuli is intensively perused in the literature for various purposes such as controlled release. Magnetic fields have also been extensively utilized as one of the possible external stimuli. The mechanism of triggering by external magnetic fields is mainly based on heating of magnetic nanoparticles (MNPs) in high frequency oscillating magnetic fields to increase the temperature up to lower critical solution temperature of a thermoresponsive polyelectrolyte. Here we propose a novel method of stimulation by utilization of low frequency rotating magnetic fields in the range of 10-100 Hz to control the release from a hydrogel including MNPs. 2-acrylamido-2-methyl-1-propanesulfonic acid and N,N'-methylenebisacrylamide were accordingly used as the monomer and the crosslinker for preparation of hydrogel samples. An in-situ precipitation method was also adopted to synthesize MNPs inside the polymer matrix. Our preliminary results indicated the controllable release of ferricyanide anions as a model compound from previously imbibed magnetic hydrogels. The kinetics of release exhibited strong sensitivity to the frequency of the applied magnetic field and the concentration of MNPs.

2. Effect of chemical treatment on properties of boron and nitrogen co-doped single-walled carbon nanotubes

Mahyar Mohammaznezhad, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Federico Rosei) We present three efficient approaches to achieve high-purity and homogeneous boron and nitrogen co-doped single-walled carbon nanotubes (SWCNT) in a high vacuum chemical vapor deposition (CVD) system. A specially designed substitution process was used to produce nanotubes with high percentage of boron and nitrogen. Doping processes with solid, liquid and solid-liquid condition were optimized for the optimal preferred doped carbon nanotubes. To estimate the doping level and crystal quality, we compared the Raman spectra with pure single wall carbon nanotubes. X-ray photoelectron spectroscopy analysis reveals the presence of substitutional boron and nitrogen atoms incorporated on the tubes. Experimental results showed that by varying the process condition, the nitrogen and boron content of the nanotubes could be altered. Moreover, we show that the diameter of the individual nanotubes was similar to the diameter of the starting nanotubes. Raman analysis shows that the intensity ratio of D to G bands (ID/IG) of nanotubes increases with the B2O3 amount and position of G-band undergoes a down-shift due to increasing doping level. XPS and Raman spectroscopy characterization indicated that the doping method had effect on the percentage of inclusion and defects. Based on our results, one can obtain materials with the desired characteristics by choosing the appropriate synthesis conditions.

3. A Monodisperse DNA Nanoparticle Platform for Delivery of Chronic Lymphocytic Leukemia Small Molecule Drugs

Danny Bousmail, McGill University (Hanadi Sleiman) Despite numerous recent breakthrough discoveries, many new drug candidates fail to reach the clinic because of their systemic toxicity, poor pharmacokinetics and off-target effects. Several drug delivery nanocarriers have been employed to aid small-molecule drug delivery and overcome these challenges. Unfortunately, most nanostructures in use are polydisperse, their size and shape can be only coarsely tuned and large-scale synthesis suffers from batch to batch variability. Therefore, control of structure and particle


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monodispersity is essential to the translation of nanomaterial drug carriers from the lab to the clinic. Our group has recently reported a modular approach to generate sequence-defined DNA-polymer conjugates. Upon self-assembly, these DNA amphiphiles form structurally-defined and monodisperse micelles. The potential of these novel DNA nanoparticles to serve as vehicles for targeted drug delivery to Chronic Lymphocytic Leukemia (CLL) is investigated. Our work to help overcome some of the limitations of other drug delivery systems will be explored in the delivery of BKM120, a class I PI3Kinase inhibitor under clinical trials for CLL treatment. BKM120 has adverse side effects in patients, most disturbing being depression; its encapsulation can potentially prevent central nervous system delivery and avoid this devastating side effect. Here, we report the development of a drug delivery platform that encapsulates BKM120 and targets it to CLL tumor cells. Structural characterization of drug-loaded micelles and drug-release kinetics studies of BKM120 reflect the morphological integrity and highly efficient drug entrapment in the DNA micelles. Fluorescence microscopy reveals enhanced uptake of DNA micelles in human cervical cancer cells and localization in the cytoplasm with no observed toxicity. In vitro studies on primary BCLL lymphocytes and HeLa cells show high efficiency of BKM120-micelle at inducing apoptosis. In vivo studies on animal models show long circulation times and full-body distribution of DNA micelles. This robust system could serve as a potential anticancer strategy for increased efficacy and reduced side-effects.

4. Novel method to photocure epoxy using semiconducting nano particles Keroles Riad, Concordia University (Paula Wood-Adams) Semiconducting nano particles have been shown to be able to photocure acrylic resins via a reduction reaction. However, epoxy conventionally photocures via a cationic process using cationic initiators. There is a research drive to optimize the ability to tune the wavelengths that can be used to photocure epoxy molecules for optimal use in coating and 3D printing. In this work, we use similar principles used in photocuring acrylics to allow semiconducting nano particles to photocure epoxy for the first time. Semiconducting nano particles can be transformed to quantum dots with tuneable absorbance wavelength by tuning their size.

5. Two way reversible shape memory with tunable actuation temperatures Kaojin Wang, University of Montreal (Julian Zhu) To design two-way reversible shape memory polymers, we synthesized a series of random copolymers by the copolymerization of ω-pentadecalactone (PDL) and ε-caprolactone (CL) with the help of Candida antarctica lipase B. P(CL-PDL) copolymers can cocrystallize over the whole composition range. The melting temperatures of copolymers increase with the composition of PPDL. For the cross-linking of these polymers, we grafted methacrylic unit as terminated groups. These macromonomers are further polymerized via irradiation with light at 365 nm to obtain cross-linked networks with different weight ratios of PCL and P(CL-PDL) copolymer. These polymer networks manifested two-way reversible dual (stress-free) and triple shape memory effects (with external stress).

6. Conception de matériaux possédant des propriétés thermiques et mécanique hors norme à partir polynorbornène acide

Barbara Martin, Université de Sherbrooke (Jérôme Claverie) Le polynorbornène acide, PNBE(COOH), possède des propriétés de dispersion, thermiques et mécaniques hors norme et est synthétisé grâce à une chimie respectueuse de l'environnement, ce qui en fait un polymère de choix pour de nombreuses applications. Le PNBE(COOH) possède toutes les propriétés du polynorbornène, c'est-à-dire qu'il a une température de transition vitreuse très haute, une haute stabilité chimique, d'excellentes propriétés optiques. Il est synthétisé en deux étapes simples à partir d'une réaction de Diels-Alder, sans solvant, avec un rendement élevé et des réactifs en majorités biosourcés et peu coûteux.


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Le PNBE(COOH) est soluble dans l'eau, ce qui nous permet de faire des thermodurcissables en milieu aqueux qui possèdent d'excellentes propriétés thermiques et mécaniques ainsi qu'un faible gonflement en milieu organique. Il peut disperser de manière très stable des nanotubes de carbone, ce qui nous a permis de faire des films, des revêtements, des fibres ou des encres conductrices tout en conservant des propriétés mécaniques et thermiques élevées. Et nous avons également pu disperser de la glaise pour créer des barrières imperméables pour des films alimentaires par exemple.

7. Preliminary cytotoxicity study of biodegradable metals on normal human urothelial cells for urinary stent application

Devi Paramitha, Université Laval (Hendra Hermawan) Urinary tract is susceptible to obstruction which can lead to severe kidney failure. The obstruction can be relieved either by surgery or implanting a small metal or plastic tube called stent inside the tract. The most common problems arise from the stenting are infection, restenosis and the need of removal procedure which increase patient morbidity and cause economic losses. A biodegradable stent with inherent strength is required to overcome those problems. Magnesium (Mg), zinc (Zn) and their alloys were proposed as the material for biodegradable metal urinary stent. An adequate information about in vitro cytocompatibility of those metals is essential to develop the new stent. In this study, normal human primary urothelial cells were exposed by 72 hours incubation of metal extracts. Their inhibition concentration 50 (IC-50) value was then estimated by mitochondrial metabolic activity WST-1 assay at day 1. The results show that Zn-based alloy has the lowest IC-50 value, followed by pure Mg, pure Zn and Mg-based alloy. This findings will be useful to determine further manipulations that are needed and to select the specifically compatible material compositions to the urothelial cells. This study will proof the concept of biodegradable metals on urinary application and open the possibility of developing new product for medical purpose.

8. Rationalising the effect of the synthesis parameters in the synthesis of CuInS2 quantum dots Riccardo Marin, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Fiorenzo Vetrone) CuInS2 (CIS) quantum dots (QDs) made a major breakthrough in the semiconductor community due to their inherent environmental friendliness, due to the lack of hazardous elements, and their remarkable optical properties which can be nowadays finely tailored throughout the whole visible-near infrared spectrum. These features are opening up a number of possible applications for these QDs, such as in the photovoltaic field, bio-sensoring, and illuminaton to name few. Although much attention has been devoted to the improvement of the synthesis protocols and interpretation of the emission mechanism of these nanoparticles, there are still many points which need to be rationalised. One of the most exploited and simplest synthesis protocol for the production of high quality CIS QDs consist in a one pot thermal decomposition of metal-organic intermediates. The use of different solvents, ligands, and metal precursors are known to lead to different final properties of the quantum dots. In this study we investigated the effect of different precursors on the optical and morphological properties of CIS QDs produced via the thermal decomposition of metal-thiolates. Combining the information obtained from optical measurements, X-ray Powder Diffraction, X-ray Photoemission Spectroscopy, and Electron Microscopy, we highlighted the effect of the anions which are present in the solution. In particular, we disclosed a trend which depends on the different size and polarizability of different halogen anions (Hofmeister series-like effect). These information would be beneficial for the rational design of high quality CIS QDs synthesis protocols.


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9. L'ingénierie de surface pour des applications biomédicales Laurence Padiolleau, Université Laval (Gaétan Laroche) La modification des propriétés de surface d'un matériau sans altérer ses propriétés intrinsèques est un réel défi dans de nombreux domaines d'applications à l'heure actuelle. Le Laboratoire d'Ingénierie de Surface (LIS) développe de nouvelles stratégies de modifications de surface et des technologies innovatrices de caractérisation de surfaces. Parmi ces techniques, le plasma froid à pression atmosphérique, contrôlés par des barrières diélectriques, permet de conférer des propriétés anti-buées et auto-nettoyantes à des surfaces de verre ou d'améliorer la biocompatibilité, aujourd'hui limitées, des prothèses artérielles synthétiques de petits diamètres en déposant un système à libération contrôlée de principes actifs sur la surface interne des prothèses. Cependant, la compréhension et l'optimisation des réactions plasma-surface ne sont possibles que si les caractéristiques du plasma sont reliées avec la composition chimique de la surface modifiée. Dans cette optique, les paramètres clés du plasma, comme la concentration des espèces chimiques, leur énergie, la densité électronique et la température, sont mesurées par spectroscopie d'émission optique afin d'établir un modèle mathématique corrélant ces paramètres clés à la composition chimique de la surface modifiée. De plus, le greffage de molécules bioactives, tels que des peptides, des principes actifs ou des protéines, à la surface des matériaux est également étudié au sein du laboratoire en utilisant différentes méthodes de greffage, tels que le plasma ou la modification chimique de surface (aminosilanisation, hydrolyse et oxydation). Ce greffage covalent permet d'améliorer l'endothélialisation et l'hémocompatibilité des biomatériaux mais aussi de reproduire le micro-environnement de cellules souches (cellules progénitrices endothéliales et cellules souches mésenchymateuses humaines) conduisant à la différentiation de ces dernières. Pour cela, des techniques de lithographie ont été adaptées afin de créer des micro-structurations de surfaces. L'expertise développée au sein du laboratoire peut être ainsi mise à profit dans des projets industriels, tel que l'amélioration de prothèses orthopédiques.

10. Towards Heat-Free Hyperspectral Near-Infrared Excited Nanoprobes: The Magic of Collective Rare-Earth Doping

Artiom Skripka, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Fiorenzo Vetrone) Rare-earth doped nanoparticles are being intensively investigated as possible imaging agents for biological and medical applications. Due to their unique physical properties it is possible to obtain visible light emission while exciting with lower energy infrared light through a process of upconversion. Upconversion emitted light can be then used for initiation of different photoprocesses in the vicinity of the nanoparticle, environmental sensing or cell imaging and tracking. Additionally, rare-earth ions have intense emissions in the near-infrared spectral region, which in turn provide deep tissue imaging, where light tissue interactions are minimal. This wide spectrum of emitted light is usually achieved via single excitation wavelength of 980 nm, which is absorbed by Yb3+ ions acting as sensitizers that then transfer the excitation energy to different activator ions constituting the nanoparticle. However, it is now being argued that due to the strong absorption of 980 nm light by water present in biological media undesirable heating effects can be induced, leading to variations of emitted light and possible thermal damage. Thus rare-earth nanoparticles that can be efficiently excited with near-infrared light, without the significant generation of heat are needed. Core/shell NaGdF4 nanoparticles doped with Er3+, Ho3+, Yb3+ in the core and Nd3+,Yb3+ in the shell were synthesized and rendered water dispersible, where a pair of sensitizer ions Nd3+ and Yb3+ are used to excite upconversion and near-infrared emitting Er3+ and Ho3+ rare-earth ions. In the following scheme Nd3+ acts as a primary sensitizer that absorbs light of around 800 nm wavelength, where water absorption is minimal and undesirable heating effects could be avoided. Upon Nd3+ excitation the energy is then passed to Yb3+ as a secondary sensitized, which then promotes the population of higher energy levels of Er3+ and Ho3+. Different emissions of such nanoparticles were thus recorded and compared upon excitation of either 980 nm or 806


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nm light, in order to establish their possibilities as biomedical imaging agents using heat-free 806 nm excitation light.

11. Highly Efficient Photoelectrochemical Cells for Solar Hydrogen Generation based on Giant Quantum Dots

Rajesh Adhikari, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Federico Rosei) Quantum dot (QD) sensitized TiO2 is considered a highly promising photoanode material for photoelectrochemical (PEC) solar hydrogen production. However, due to its limited stability, the photoanode suffers from degradation of its long-term PEC performance. Here, we will report the design and characterization of a high-efficiency and long-term stable Pt-free PEC cell. The photoanode is composed of a mesoporous TiO2 nanoparticle film sensitized with 'giant' core@shell QDs for PEC solar hydrogen generation. The thick shell enhances light absorption in the visible range, increases the stability of the QDs and does not inhibit charge separation, injection and transport, needed for proper operation of the device. We obtained an unprecedented photocurrent density (~10 mA/cm2) for 'giant' QDs based PEC devices and a very promising stability, indicating that the proposed cell architecture is a good candidate for long-term stable QD-based PEC solar hydrogen generation

12. Atomistic Study of the Self-Assembly Mechanism in Dilute Regime of Lyotropic Chromonic Liquid Crystals

Oscar Manuel Matus Rivas, McGill University (Alejandro Rey) Graphene exhibits a collection of unique chemical, mechanical and electronic properties that have bolster the production of novel ordered graphenic materials, such as vertically aligned graphene films (VAGF) on substrates. VAGF can be an alternative to fabricate graphene nanoribbons and nanopores, hydrophobic or hydrophilic coatings, high-redox-activity electrode surfaces or even to synthesize chemically patterned surfaces for cell adhesion and guidance. These structures can be obtained at room temperature from a liquid crystal precursor, namely Lyotropic Chromonic Liquid Crystals (LCLC). LCLC are non-amphiphilic sulfonated polyaromatic food coloring dyes that self-assembly into aggregates of varying size in aqueous solution. In this research, we present an atomistic investigation of the self-assembly mechanism of LCLC using molecular dynamics and metadynamics simulations in dilute regime for Disodium Cromoglycate (DSCG) system. The self-assembly behavior of LCLC is reproduced accurately. Also, a stacking model for DSCG is proposed where the role of hydrogen bonding stabilization is discussed. These results shed light on the LCLC aggregation mechanism which is believed to be isodesmic.

13. Improved photovoltaic performance of dye sensitized solar cells with surface modified SnO2 photoanodes

Kaustubh Basu, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Fiorenzo Vetrone) Dye sensitized solar cells (DSSCs) have been widely explored over the past two decades as a potential alternative to conventional silicon photovoltaic (PV) devices because of their low cost, abundance of raw material, facile fabrication process and overall reasonable PV performance (record efficiency above 14%).[1,2] TiO2 nanoparticle films have been widely used as photoanodes in DSSCs thanks to the very fast electron injection rates from the excited state of the dye into the TiO2 nanoparticle conduction band. However, due to limited electron mobility in TiO2, high electron recombination rate leads to degradation of photoconversion efficiency (PCE).[3] SnO2 on the other hand, is a promising oxide material because of its higher electronic mobility and large band gap (3.8 eV).[4] The mobilities reported in both single crystal SnO2[5] as well as nanostructures[6] are orders


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of magnitude higher than in single crystal TiO2.3 The high electron mobility in SnO2 compared to its counterpart TiO2, leads to faster diffusion-mediated transport of photoinjected electrons. The wider bandgap of SnO2, compared to anatase TiO2 (3.2 eV) creates fewer oxidative holes in the valance band under UV illumination, so as to minimize dye degradation rate and long term stability of DSSCs.[7] Herein, we report the fabrication and testing of DSSCs based on SnO2 nanoparticles of average size ~20 nm. Fluorine-doped Tin oxide (FTO) conducting glass substrates were treated with TiOx or TiCl4 precursor solutions to create a blocking layer before tape casting the SnO2 mesoporous anode. In addition, SnO2 photoelectrodes were treated with the same precursor solutions to deposit a TiO2 passivating layer covering the SnO2 nanoparticles. We found that the modification enhances the short circuit current, open-circuit voltage, and fill factor, leading to nearly 2-fold increase in PCE, from 1.48% without any treatment, to 2.85% achieved with TiCl4 treatment. The superior PV performance of the DSSCs assembled with modified photoanode is attributed to enhanced electron lifetime and suppression of electron recombination to the electrolyte, as confirmed by electrochemical impedance spectroscopy. These results indicate that modification of the FTO and SnO2 anode by titania can play a major role in maximizing the PCE.

1. Gratzel, M. Nature 414, 338-344 (2001). 2. Hagfeldt, A., Boschloo, G., Sun, L., Kloo, L. & Pettersson, H. Chemical Reviews 110, 6595-6663 (2010). 3. Hendry, E., Koeberg, M., O'Regan, B. & Bonn, M. Nano Lett. 6, 755-759 (2006). 4. Gubbala, S., Chakrapani, V., Kumar, V. & Sunkara, M. K. Band-edge engineered hybrid structures for dye-sensitized solar cells based

on SnO2 nanowires. Advanced Functional Materials 18, 2411-2418 (2008). 5. Jarzebski, Z. M. & Marton, J. P. Journal of The Electrochemical Society 123, 299C-310C (1976). 6. Arnold, M. S., Avouris, P., Pan, Z. W. & Wang, Z. L. The Journal of Physical Chemistry B 107, 659-663 (2002). 7. Shang, G. et al. Journal of Materials Chemistry 22, 25335-25339 (2012).

14. AFM-IR: a new tool for nanoscale chemical characterization of polymer materials Phuong Nguyen Tri, Université de Montréal (Robert E. Prud'homme) FT- IR is one of the most powerful techniques for analysing of polymer structure but its low spatial resolution [three times the wavelength of the IR radiations (10-30 µm)] restricts its expansion for several specific applications. However, the AFM-IR (NanoIR) can provide high resolution topography images, of the order of 50-100 nm, and local chemical composition below the diffraction limit, as well as perform nanoscale mechanical and thermal analysis by using a photothermal technique. In this presentation, we would like to provide some useful examples of the use of AFM-IR, from the literature and from own work, dealing with polymer composites, polymer blends, multilayers, and biomaterials.

15. Development of bile acid-based nanoparticles for biomedical applications Alexander Cunningham, University of Montreal (Julian Zhu) Physico-chemical properties frequently limit the use of recently discovered therapeutic molecules. To circumvent these issues, the use of drug delivery nanocarriers enables the safe and efficient spatiotemporal delivery of therapeutic molecules. Despite the breadth of research on the topic, very few successful polymer-based drug delivery systems are currently on the market due to incomplete biocompatibility or inefficient drug encapsulation as well as unstable formulations. Bile acid-based amphiphilic block copolymers offer a promising solution. Bile acids are excellent candidates for biomaterials due to their non-toxicity, amphiphilic properties, their relative abundance in nature, and the convenience of chemical modifications. Specifically, poly(ethylene glycol) and poly(allyl glycidyl ether) of various chain lengths were synthesized via anionic ring-opening polymerization from the hydroxyl groups of bile acid to help in the flexibility and stability of the micelles for dual drug and gene delivery directed towards anti-cancer treatment.


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16. Controlling Lateral Spacing In Phenolic Surfactant Monolayers At The Air Water Interface Renaud Miclette Lamarche, Concordia University (Christine DeWolf) Phenolic compounds such as tannins exhibit antioxidant, metal chelating and protein-binding abilities; surfactants with this functionality may confer these properties to self-assembled structures and surfaces. We have previously shown the phenolic headgroup to be extremely self-adhesive give strong lateral rigidity to monolayers at liquid surfaces. The extent to which the phase behaviour can be tuned by modifying the intermolecular interactions via changes in subphase composition (such as pH, salt concentration and temperature) will be presented for lauryl gallate (C12) and octadecylgallate (C18) surfactants which exhibit liquid expanded and condensed phases, respectively, at the air water interface. The film organizational changes are determined by grazing incidence x-ray diffraction (GIXD) while morphology is assessed using Brewster angle microscopy at the air-water interface and atomic force microscopy for films deposited on mica. The competition of hydrogen-bonding and π-stacking interactions between headgroups can be manipulated to yield highly directional domain growth and control over the inter-surfactant distance. Contrary to what is observed for most surfactant monolayers, GIXD measurements show that the gallate headgroups are arranged in a crystalline packing state with limited free rotation, attributed to strong hydrogen bonding and π-stacking interactions of the gallate headgroup. The combination of parameters required to modify this preferred headgroup arrangement will be discussed. An understanding of the impact of these parameters on film organization is essential for the design of functional surface coatings.

17. Ultra-high Tg functionalized fibers via electrospinning of polynorbornene Assad Moubarak Compaore, Université du Québec à Montréal (Jérôme Claverie) Les polynorbornènes obtenu par le mécanisme de polymérisation catalytique avec rectification et insertion de norbornène sont des polymères qui présentent de bonnes propriétés thermique et mécanique. Leur température de transition vitreuse est très haute (350 °C). Une particularité de ces polymères est leur capacité à être électro-filé par le procédé d'Electrospinning. Des fibres rigides de diamètre micrométrique (2 à 8 µm) sont ainsi obtenu dans l'optique d'en faire des matériaux de renfort pour les composites polymères. La température de dégradation de ces fibres thermodurcissables est de 350 °C.

18. Morphological Instabilities and Surface Wrinkling in Cholesteric Liquid Crystal Membranes Pardis Rofouieerahi, McGill University We present a physical model to investigate the formation of the periodic patterns in biological materials through the interaction of anisotropic interfacial tension, bending elasticity, and capillarity at free surfaces. Focusing on the cellulosic cholesteric liquid crystal (CCLC) material model, the generalized shape equation for anisotropic interfaces using the Cahn-Hoffman capillarity vector, the Rapini-Papoular anchoring energy, and Helfrich free energy are applied to analyze periodic nano-wrinkling in plant-based plywood free surfaces. The model incorporates liquid crystal anisotropy into classical elastic membrane mechanics. At negligible bending elasticity, the model predicts a regular pattern of sinusoidal wrinkles. While, in the presence of bending elasticity, the membrane shape exhibits multiple-length scale periodic wrinkles induced by the intrinsic nonlinearity of the elasticity equations. The results can be used for investigating the interaction of interfacial anchoring and bending in forming the complex nonlinear patterns.


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19. Upconverting Nanoparticles Used As Multifunctional Nanocomposites Combining With Photothermal and Photodynamic Effects

Yue Huang, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Fiorenzo Vetrone) Lanthanide-doped upconverting nanoparticles (UCNPs) are well known in biological applications due to their unique optical properties by converting near-infrared light to visible light. Combining with a variety of therapeutic models based on the UCNPs has become a new concept to obtain diagnostics and therapies in the field of cancer treatment. Herein, we develop a novel multifunctional nanocomposite consisting of UCNPs, gold nanorods (GNRs), silica (SiO2), and photosensitizers (GNRs@SiO2@UCNPs@ZnPC), with highly integrated functionalities including luminescence image, photothermal effect and photodynamic effect. Under exposure of laser irradiation, UCNPs and GNRs could be excited simultaneously, owing to the surface plasmon resonance (SPR) of the GNRs was overlap with the Yb3+ absorption at 980 nm. The ratio of intensity of green emission of UCNPs is sensitive to temperature, which can be used to calculate the temperature change due to heat production from the GNRs. Furthermore, aluminescence enhancement is observed when compared with bare UCNPs due to the localized field created by the GNRs, which influence the luminescence intensity of UCNPs. Finally, a photosensitizer, zinc phthalocyanine, was loaded into the mesoporous silica. Upon the laser irradiation, UCNPs absorbed near-infrared light to convert to visible light, subsequently activate the photosensitizer to release singlet oxygen for future applications in photodynamic therapy. This makes the photodynamic therapy occurred in deep tissue. Therefore, such multifunctional nanocomposites, which not only well suited for bioimaging, but also providing photothermal and photodynamic effects, shows strong potential in cancer therapy.

20. Orthogonally-assisted assembly of a long-range network of DNA nanotubes with hydrophobic pockets

Janane Rahbani, McGill University (Hanadi Sleiman) The ease of assembly, programmability, and robustness make DNA nanotubes interesting for numerous applications. We have developed a new method to grow stable nanotubes with intrinsic dynamic behavior. Our tubes are constructed by hybridizing only 11 unmodified strands via sticky-end cohesion in less than 6 hours and are designed to have a unique architecture that is capable of cooperatively amplifying a stimulus into motion. We used the strand displacement strategy both on free nanotubes in solution and immobilized tubes on a solid support as a proof of concept to examine: (i) the stability of the single-stranded version of the design, (ii) the morphological shift between the single and double-stranded forms and (iii) how fast can our system respond to a stimulus. We have also developed a simple method to functionalize our tubes at different regions with hydrophobic polymers via phosphoramidite chemistry. DNA nanotechnology relies on Watson-Crick base-pairing to guide the assembly of its nanostructures. While the structural control of this approach is remarkable, it is inherently limited by the four-letter genetic code. Ongoing efforts have focused on introducing orthogonal interactions to increase the complexity and functional range of DNA structures. Inspired by synthetic amphiphilic block copolymers that are capable of organizing into numerous morphologies, hydrophobic modifications on DNA have been employed to trigger their assembly into higher-order structures.

21. Decorating DNA cages to control cellular recognition and uptake Aurelie Lacroix, McGill University (Hanadi Sleiman) Using DNA as a building block to construct highly programmable nanostructures offers opportunities to develop novel drug delivery systems. Our group has successfully built DNA constructs that can release therapeutics under specific conditions. However, challenges concerning their cellular uptake still need to be addressed, such as the use of cytotoxic transfection agents. By decorating our structures with different


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ligands, we aim to improve cellular recognition and uptake. Here we present two of the most promising strategies we are currently pursuing. First, we decorated DNA cubes with a DNA aptamer specifically targeting surface receptor of Burkitt lymphomas cells. The aptamer was loaded at different positions on the cube and we manage to position up to 8 aptamers per construct. We studied binding by fluorescence microscopy. We observed improved stability of the aptamer once placed on the cube with a concomitant increase in targeting and binding to cells. In another strategy, we conjugated dendritic-alkyl chains to DNA (D-DNA) to engineer interactions with serum proteins, primarily albumin. Because it is the major protein in blood and it accumulates around cancer tissues, we believe it can be used as a carrier for DNA nanostructures. Efficient binding of these DNA amphiphilic constructs (single strand DNA, and DNA cube) to albumin was demonstrated by electrophoretic mobility shift assays. Additionally, degradation of DNA strands bound to albumin in serum was shown to be significantly slowed.

22. Core-Shell Magnetic Nanoparticles Tagged with Cyclometalated Heteroleptic Iridium Pendants for the Generation of Reactive Oxygen Species

Joe Gerald Jesu Raj, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Fiorenzo Vetrone) Super paramagnetic iron oxide nanoparticles (SPION) have gained much attention recently for various biomedical applications owing to their biocompatibility, ease of surface functionalization and paramagnetic properties. Magnetic properties of these iron oxide nanoparticles could be controlled by the application of an external magnetic field. This paves the way for targeted drug delivery on the cancer cells by drug-encapsulated magnetic core by changing the applied magnetic field. In our present work, we have synthesized an integrated multi-modal nanoprobe that consists of a highly photoluminescent iridium complex integrated on the surface of silica coated magnetic nanoparticles. The production of ROS is vital in applications with regard to surface oncology. Further investigation is being carried out in our laboratory. Overall, this iridium complex decorated magnetic nanoparticle system offers multiple applications such as imaging, and ROS generation hence could be used as a multi-modal nanoprobe.

23. Effect of Hot-injection Temperature on Morphology of NaGdF4:Yb3+, Er3+ Nanoparticles Miao Wang, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Fiorenzo Vetrone) Objectives: The synthesis of luminescent upconverting NaGdF4 nanoplates via co-thermolysis of NaCF3COO and Gd(CF3COO)3 has been well established. The objective of this study is to synthesize high quality NaGdF4:Yb3+ (20%), Er3+ (2%) upconverting nanoparticles (UCNPs) with various morphology (nanorods, nanospheres, nanoplates and nanodisks) by modifying the hot-injection thermolysis strategy established by our group, and investigate the anisotropic growth and shape evolution of β-NaGdF4 to study the principle of diverse morphology formation. Methods: NaGdF4:Yb3+, Er3+ (20%, 2% doping, respectively) UCNPs with various morphologies were synthesized via the hot-injection thermal decomposition strategy by tuning the injecting temperature (290~320 °C) and reaction time (1~3 hours). In order to study the process of α → β phase transition and growth kinetics, 1 ml of reaction solution was taken out at predetermined intervals (20 min, 40 min, 1 h, 1.5 h, 2 h and 3 h) and characterized by X-ray Power Diffraction (XRPD), Transmission Electron Microscopy (TEM) imaging and High Resolution TEM (HRTEM). The upconversion luminescence spectroscopy of the synthesized UCNPs was measured under 980 nm excitation light. Results and Discussion: Monodispersed β-NaGdF4:Yb3+, Er3+ UCNPs with various sizes (20-70 nm) and morphologies, including nanorods, nanospheres, nanoprisms, nanoplates and nanodisks have been successfully synthesized by tuning the injecting temperature and reaction time. XRD analysis revealed the correlation between the particle shape and the preferential sitting position (either side face or bottom face)


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against the loading substrate. The different supersaturation of precursors caused by the different injecting temperature played an important role in the crystal nucleation and growth process. The UCNPs were all formed via α to β-phase transition. Nanorods underwent a two-stage phase transition: Ostwald ripening dominated at the beginning of the α → β transition due to the broad size distribution of the particles. With increasing monomer concentration, the Ostwald ripening was restricted and the growth of UCNPs along the c-axis (1-dimention growth) was promoted due to their accelerated growth rate at high monomer concentration. The pure β-phase nanorods were finally formed via the diffusion controlled restricted Ostwald ripening. Nanoplates were grown via the enhanced Ostwald ripening due to the relatively lower monomer concentration in comparison with the case of the formation of the rods. With extension of the reaction time, the hexagonal nanoprisms and nanoplates transferred to nanospheres and nanodisks, respectively, due to intra-particle diffusion process. The upconversion luminescence (UCPL) intensity and the ratio of green to red emission not only correlated to the particles size but also related to the aspect ratio of UCNPs. Conclusion: Our work has demonstrated that controlling the injecting temperature and reaction time could be an effective approach to control the morphology of β-NaGdF4: Yb3+, Er3+ UCNPs. The different supersaturation caused at the different injecting temperatures could directly control the Ostwald ripening rate during the phase transition, and consequently affected the morphology, uniformity and monodispersity of UCNPs. The UCPL spectra displayed different characteristics based on the morphology of the UCNPs.

24. Formation of Molecular Hydrogels from a Bile Acid Derivative and Selected Carboxylic Acids Meng Zhang, Université de Montréal (Julian Zhu) Bile acids are natural compounds that can be made into dimers by covalently linking two of them through diethylenetriamine. A cholic acid dimer of this kind is synthesized and is found to form thermally reversible hydrogels with selected carboxylic acids through combined hydrogen bonding and ionic interactions. The gelation and viscoelastic properties of the hydrogels may be varied by judicious choice of the carboxylic mono- and diacids. The total organic content (the dimer and carboxylic acid) represents about 2% or less by weight in the ternary mixture. The molecular arrangement between the dimer and carboxylic acid is proposed to illustrate the formation mechanism of the hydrogels. The marginal solubility of the dimer-acid mixtures seems to be the deciding factor in obtaining the hydrogels.

25. Adsorption on highly microporous adsorbents for storage and separation applications David Durette, Université du Québec à Trois-Rivières (Pierre Bénard) The physisorption of gases on highly microporous adsorbent can be used in several energy and environmental applications such as the low pressure, high density storage of gaseous fuels (hydrogen, methane) and the purification and separation of gases (upgrading of biogas to biomethane, hydrogen purification). We present an overview of the research activities of our research group relevant to renewable energy applications based on supercritical adsorption processes. The adsorption isotherms of hydrogen and gas mixtures representative of biogas composition on highly microporous adsorbents such as metal-organic frameworks and carbon nanostructures are studied using statistical physics simulations (Grand Canonical Monte Carlo) and density functional theory/pore volume-based approaches. We also discuss the kinetics of the adsorption process in adsorption columns used for gas separation. Experimental measurements of thermodynamic and kinetic adsorption properties such as the adsorption isotherms of hydrogen and other gases, the specific enthalpy of adsorption and the breakthrough curves are also discussed.

26. Multifunctional Carbon Electrode for Electrochemical Double Layer Capacitors Birhanu Desalegn Assresahegn, Université du Québec à Montréal (Daniel Bélanger) Multifunctional carbon materials are prepared for application as active electrode material in electrochemical capacitor displaying both charge storage and binder properties. The synthesis of the materials involves the


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functionalization of high surface area Black Pearls 2000 carbon black by covalent attachment of polyacrylic acid. The polyacrylic acid polymer is formed by atom transfer radical polymerization using 1-(bromoethyl)benzene groups initially bonded to the carbon by spontaneous grafting from the corresponding diazonium ions. The grafting of 1-(bromoethyl)benzene and polyacrylic acid is confirmed by thermogravimetric analysis, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy and nitrogen gas adsorption isotherm. The composite electrode films prepared from the modified carbon are more hydrophilic and have better wettability in aqueous electrolyte than the one prepared with the unmodified carbon. The modified electrodes also show a higher specific capacitance (ca. 140 F.g-1), a wider working potential window (1.5 V) and excellent specific capacitance retention upon cycling (99.9% after 5000 cycles) in aqueous 0.65 M K2SO4 electrolyte. Moreover, a relatively high specific capacitance (ca. 90 F.g-

1) is maintained at a scan rate of 1000 mV.s-1 with the polyacrylic acid modified carbon electrode.

27. Ab initio interstitial hydrogen diffusion and electronic behavior in CuPd alloys Rodrigo Monteiro de Oliveira, Université du Québec à Trois-Rivières (Pierre Benard) Hydrogen gas is a promising energy vector to achieve a clean energy, bypassing problems created by fossil fuels, but the high production cost remains as an important barrier to be solved, principally in purification stages[1]. Metallic membranes can be used to purify hydrogen to a level that makes it compatible for PEM fuel cells applications. Hydruration, high selectivity and transport properties of Palladium, constitute itself an excellent candidate material for such membranes[2]. The high cost of Pd is, however, an impediment to the development of this technology. Reducing the Pd concentration by alloying with compatible metals offers an outstanding pathway to make this technology more affordable. Pd-Cu alloys present increased sulfur resistance and good thermal resilience compared with pure Pd membranes[3,4,5]. We examine the structural and electronic properties of Pd-Cu alloys from first principle calculations using DFT (Density Functional Theory) as implemented in VASP (Vienna Ab Initio Simulation Package)[6,7,8]. NEB simulations are also performed to describe the energy barriers associated with atomic hydrogen motion between interstitial sites[9].

1. Bruno Honrado Guerreiro, Manuel. H. Martin, Lionel Roue, and Daniel Guay. J. Phys. Chem. C, 120:5297-5307, 2016. 2. T. L. Ward and T. Dao, Journal of Membrane Science, 1999, 153, 211-231. 3. F. Roa, M. J. Block and J. Way, Desalination, 2002, 147, 411-416. 4. S.-E. Nam and K.-H. Lee, Journal of Membrane Science, 2002, 192, 177-185. 5. B. C. Nielsen, Ö. N. Dogan and B. H. Howard, Corrosion Sci., 2015, 96, 74-86. 6. G. Kresse and J. Furthmuller, Phys. Rev. B, 1996, 54, 169-186. 7. G. Kresse and J. Furthmuller, Comput. Mater. Sci., 1996, 6, 15-50. 8. G. Kresse and J. Furthmuller, Phys. Rev. B, 1993, 47, 558-561. 9. J. M. Rowe, J. J. Rush, L. A. de Graaf and G. A. Ferguson, PHYSICAL REVIEW LETTERS, 1972, 29, 1250-1253.

28. Exploring the Chirality of Tri-O-Thymotide Inclusion Compounds with Achiral Guest Florence Victoria, Concordia University (Louis Cuccia) Tri-O-thymotide (TOT) is a widely studied host in the formation of inclusion compounds. The fascination of TOT resides in its capability to form inclusion compounds with a wide variety of guests. Interestingly, TOT, an achiral molecule, can sometimes form chiral inclusion compounds with achiral guests (i.e. spontaneous resolution). The goal of our project is to better understand conglomerate crystallization and crystal transformations of TOT inclusion compounds using solid-state circular dichroism, powder x-ray diffraction and thermogravimetric analysis. Attrition-enhanced chiral amplification (i.e. Viedma ripening) in conglomerate TOT inclusion compounds has also been explored.


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29. Polypyridine functionalized polyoxometalates as platform for Re(CO)3(diimine) complexes Thomas Auvray, Université de Montréal (Garry S. Hanan) Our group is interested in the design of efficient light harvesting species to convert solar energy into chemical energy. One of our approach is to combine the well-known [Re(CO)3Br(bpy)] photosensitizer with polyoxometalates, a family of anionic oxoclusters known for its electron reservoir properties. Different polypyridine ligands covalently grafted on a Dawson type polyoxometalate are used as ligands for Re(I) complexation. The properties of the different species are described in the poster.

30. CSACS Surface Probe Microscopy Facility Mohini Ramkaran, McGill University (CSACS) Since 2011, the CSACS SPM facility offers services to the academic and industrial scientific community on surface probe microscopy. Research professionals provide training, continuous support and analyses of a wide range of samples. Here we describe the various SPM techniques that include imaging, friction and nanomechanical measurements in a variety of environmental conditions our SPM installations has to offer.

31. Design and formation of two-dimensional ordered organic network Gianluca Galeotti, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Federico Rosei) The progressive miniaturization of electronic devices, together with the reduction of the cost are the driving forces of the nanoelectronics. To reach these goals, the challenge is to make cheap and environmental friendly nanomaterials which can be integrated in nanodevices. Conductive polymers are one of the best candidate class of materials for solving this issue. These organic materials own the properties, which can be easily tuned, that make them potentially excellent to design and form cheap nanomaterials. The only natural two-dimensional (2D) material is graphene which has limitation due to its zero bandgap. Therefore, using organic molecules with various functional groups, a wide class of conductive polymers with selected properties could be designed and realized, using surfaces as templates to constrain the 2D growth. However, both the properties and the goodness of these materials will depend on the molecule-surface and molecule-molecule interactions, and therefore the functional groups present on the molecule will steer the final self-assembled structure obtained. To accomplish these goals, it is essential to deeply understand the adsorption of the molecules with multiple reactive sites. From the broad range of chemicals with different termination groups, we chose to study TBrTTB, a threefold symmetric halogen-containing molecule which can obtain reactive site upon adsorption on the transition metal surfaces, following the formation of a network through Ullmann carbon-carbon coupling. In addition, the presence of thiophene ring (containing sulfur) in the molecule would grant favorable electronic properties in terms of building a conjugated network. Here, we report the study of the self-assembly of TBrTTB on different transition metal surfaces, Cu(111), Ag(111) and Au(111), by scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). Due to the sulfur atoms disposition, when adsorbed on the surface, TBrTTB presents a chiral character, and therefore two different mirrored 'R for right' and 'S for left' enantiomers could be found. Formation of chiral networks adds interest to the study, and the chirality could possibly transfer from the molecule to the whole surface. This study gives an insight into the interactions of different reactive sites within TBrTTB with different surfaces. These results could be further extended in the future to design and make two-dimensional polymeric networks with tailored properties.


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32. Porous Silica Beads with a High Au Loading for Biological Applications Siting Ni, McGill University (R. Bruce Lennox) A synthetic protocol has been developed for the preparation of spherical porous silica beads with particle diameters around 5 µm and pore diameters around 20 nm. A combination of the micelle-templated and swelling agent incorporation methods has been used to achieve high porosity silica beads. 4-dimethylaminopyridine (DMAP)-coated AuNPs were embedded into the negative charged pores of the porous silica beads via electrostatic interaction. The structure of the resulting AuNP/silica beads were characterised by TEM, SEM, and UV/Vis. The AuNP/silica beads have high stability even after 17h bath sonication. The material was further coated with lipid bilayers for biological applications.

33. Multi-Functional Single-Chain Nanoparticles Based on Photo-Responsive Polymers Weizheng Fan, Université de Sherbrooke (Yue Zhao) Polymer single-chain nanoparticles (SCNPs), a class of specific nanoparticles which are formed by one polymer chain via intramolecular crosslinking-induced collapse, have generated increasing interest due to their ultrasmall size (1.5-20 nm) and related distinct properties. In our group, we are working on the photoresponsive SCNPs with new functions to extend the possibility of various applications such as drug delivery, nanoreactor and so on. In my presentation, I will report two kinds of photoresponsive functional SCNP systems. The first is a class of SCNPs based on main-chain coumarin containing polyester that exhibit photoinduced degradability and size tunability by using UV light at two different wavelengths. The second system is prepared from an azobenzene-containing liquid crystalline polymer that, in the form of cross-linked SCNPs, still retain the liquid crystal order and, more interestingly, displays photoluminescence and photoinduced deformation related to the trans-cis photoiosmerization of azobenzene mesogens.

34. The application of close-packing structures in dental composites Ruili Wang, University of Montreal (Julian Zhu) The amount of inorganic filler particles in the dental composites can help to improve mechanical properties and reduce polymerization shrinkage during their use. Efforts have been made to increase the filler particle content. We have examined the situation of close packed sphere particles and calculated the maximum amount of particles to be at 74.05%, regardless of the particle size. However, this maybe further improved by use of a mixture of micro- and nano-particles and by the use of non-spherical particles. We will show examples of these mixtures along with experimental data in our labs and in the literature. We hope that these theoretical estimation in addition to the experimental data will serve as guidelines in the design and formulation of new dental composites with better properties and improved performance.

35. Self-assembly of indoles on metal surfaces Fabrizio De Marchi, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Federico Rosei) In nature, complex systems are easily built by the self-organization of small molecular building blocks. By exploiting the self-assembling process, it would be possible to design a particular motif or engineer the dimensions of a nanostructure by simply choosing a proper set of monomers. However, it is not quite easy to precisely predict how an adsorbed molecule will interact with its neighbors or with the substrate itself. Therefore, more insight can be gathered by the systematic study of small, simple systems or molecules. We report here on the self-assembly of three simple molecules: indole 2-carboxylic acid (I2CA), 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) on various substrates including (111) facet of Au, Ag, and Cu. DHICA and DHI are the monomers that form eumelanin, a very interesting material for bioelectronics applications. After being deposited in ultra-high vacuum (UHV) condition on the above mentioned surfaces, DHICA can form a variety of different architectures, by simply varying the


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conditions used to prepare the molecular film. By investigating I2CA and DHI separately, we were able to evaluate the distinctive contribution of the carboxyl and hydroxyl group in the self-assembly process. Our data show that I2CA molecules interact with each other to form simple dimer pairs, formed by hydrogen bond of their -COOH moieties, and arrange a simple ordered pattern that is relatively independent of the substrate and preparation conditions. On the other hand, the catechol (1,2-dihydroxybenzene) group of DHI strongly interacts with the surface adatoms, which leads to the formation of a very ordered organometallic self-assembled networks. In summary, we will present the Scanning Tunneling Microscopy (STM) data to compare the self-assembled structures of each of these molecules formed on (111) Au, Ag, and Cu. Our complementary Density Functional Theory (DFT) calculations suggest the most stable geometries of these molecular structures.

36. Multi-location multiple stimuli-responsive degradation of block copolymer-based micelles for rapid and controlled release

Arman Moini Jazani, Concordia University (John Oh) Well-defined amphiphilic block copolymers and their self-assembled nanostructures designed with stimuli-responsive degradation (SRD) have emerged as promising nanocarriers for cancer therapy. SRD involves the incorporation of dynamic covalent linkages, which can be later cleaved in response to external stimuli, preferably cellular components. Thus, SRD-exhibiting nanocarriers, which are stable under physiological conditions during blood circulation, can be dissociated in a controlled fashion as cellular components provide the appropriate stimuli to trigger biodegradation in microenvironments of tumors and inside cancer cells. Exploring unique disulfide-thiol chemistry, our research group has developed various approaches that allow for the synthesis of novel block copolymers and their self-assembled nanostructures exhibiting reduction-responsive degradation, thus leading to enhanced release of encapsulated drugs. Most approaches involve the incorporation of different densities of disulfide linkages positioned at single locations and further dual locations. Recently, we have focused on an effective SRD strategy that centers on the development of new intracellular nanocarriers having multiple stimuli-responsive cleavable linkages at multiple locations, as in the micellar core, in the interlayered corona, and at the interface between the hydrophobic core and corona (denoted as ML-MSRD strategy). This new strategy dramatically increases versatility since responses to each stimulus can independently and precisely regulate release of encapsulated biomolecules at several locations. Further, the strategy enables the investigation of structure-property relationship between morphological variance and stimuli-responsive degradation. Ultimately, the results enable the optimization of degradable micelles offering enhanced release inside diseased cells, particularly targeted cancer cells.


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37. TiO2 Thick Film Sensitized With Quantum Dot Through Electrophoretic Deposition Lei Jin, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Rosei Federico) Electrophoretic deposition (EPD) is a technique based on application of an external electric field to colloidal nanoparticles (NPs) suspended in a liquid medium to induce their migration and their final grafting to a desired electrode. It has been demonstrated for preparation of high efficiency photoanodes in which QDs are grafted to a mesoporous TiO2 NP thick film. As the performance of photoanodes is highly dependent on not only the loading amounts, but also the QDs dispersion in TiO2 film, it is very important to control the QDs loading process, while a systematic investigation of the physical chemical QD loading dynamic by EPD is still missing. Here, for the first time, we systematically investigated the dynamics of near infrared QDs loaded into TiO2 mesoporous film via EPD, including the determination of the main parameters regulating the process. In addition, we also demonstrated the increased stability of the core/shell structure compared to PbS QDs after EPD in terms of structure and optical properties. Considering our previous study confirmed a fast charge transfer from PbS/CdS to TiO2, QD sensitized TiO2 can be strong candidates for the development of highly efficient and stable photoanodes in PV devices and H2 generation through water splitting.

38. Investigation of Host/Guest structures based on Covalent Organic Frameworks Daling Cui, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Federico Rosei) To date, the production of porous templates for two-dimensional host/guest (H/G) structures at surfaces has primarily focused on self-assembly based on non-covalent interactions,[1] and the formation and characterization of these H/G networks has been carried out under ultra-high vacuum (UHV)[2-5] conditions or at the solid-liquid interface.[6] The growth of template networks which are able to host molecules, leading to the formation of host/guest (H/G) structures, could be an important methodology for exploring crystallization in the third dimension. A key challenge of the practical applications of H/G structures is the stability of such networks under ambient conditions. Here, we report the synthesis of a H/G structure that utilizes a highly-oriented pyrolytic graphite (HOPG)-supported benzenediboronic acid (BDBA) COF, which we use as a host template. We demonstrate that this template stabilizes fullerene guests at the solid-liquid interface and in dried film.[7] Furthermore, we demonstrate that this structure can act as a foundation for growing 3D (thin film) structures of fullerene. The on-surface synthesis of covalent 2D architectures is an emerging field in nanoscience. The present study shows that COF templates can offer the possibility of forming robust frameworks for applications-driven H/G architectures and may be a useful tool for elucidating the possibilities for controlled crystallization in third dimension. We have also investigated the possibility of simultaneously introducing two types of guests to COF-1. Combining coronene and fullerene, and corannulene and fullerene in COF-1 can provide the fundamental understanding about the interactions between host and guest or interaction between two types of guest molecules. This work not only provides insights into the H/G system but also offers important information about designing nanostructure that integrates multiple components out of plane.

1. Cicoira, F., C. Santato, and F. Rosei, Two-dimensional nanotemplates as surface cues for the controlled assembly of organic molecules, in STM and AFM Studies on (Bio) molecular Systems: Unravelling the Nanoworld. 2008, Springer. p. 203-267.

2. Theobald, J.A., et al., Controlling molecular deposition and layer structure with supramolecular surface assemblies. Nature, 2003. 424(6952): p. 1029-1031.

3. Stepanow, S., et al., Steering molecular organization and host-guest interactions using two-dimensional nanoporous coordination systems. Nature Materials, 2004. 3(4): p. 229-233.

4. Griessl, S.J., et al., Incorporation and manipulation of coronene in an organic template structure. Langmuir, 2004. 20(21): p. 9403-9407.

5. Spillmann, H., et al., A Two-Dimensional Porphyrin-Based Porous Network Featuring Communicating Cavities for the Templated Complexation of Fullerenes. Advanced materials, 2006. 18(3): p. 275-279.


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6. Griessl, S.J., et al., Room-temperature scanning tunneling microscopy manipulation of single C60 molecules at the liquid-solid interface: playing nanosoccer. The Journal of Physical Chemistry B, 2004. 108(31): p. 11556-11560.

7. Cui, D., et al., Solution and air stable host/guest architectures from a single layer covalent organic framework. Chemical Communications, 2015. 51(92): p. 16510-16513.

39. Electron transfer properties of graphene-based composites electrodes Haixia Wang, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Mohamed Mohamedi) Owing to its unique properties of two-dimensional structure, high active surface area, outstanding electronic properties and excellent mechanical and thermal stability, graphene is promising as the catalyst support for fuel cells reactions. Binder-containing and binder-free graphene and graphene oxide composites of various compositions are prepared onto carbon paper (CP) substrate. In this poster, I will report the electron transfer properties and the quality of electrical contact between the graphene composites and the CP substrate in a benchmark solution of 1.0 mM K4Fe(CN)6 and 1.0 M KCl. Afterwards, Pt nanoparticles onto graphene composites have been deposited by the pulsed laser deposition (PLD) technique. Then, their catalytic properties graphene composite/Pt nanoparticles are assessed towards electrocatalysis of ethanol oxidation, one reaction that is of prime importance to direct ethanol fuel-cell technology.

40. In situ X- ray absorption studies of advanced materials for energy storage and catalytic applications

Jessica Nava, Université de Sherbrooke (Nadi Braidy) X-ray absorption spectroscopy (XAS) is an ideal tool to study the changes in the oxidation state and local coordination environment of different transition metals. Such is the case of the electrode material Na2Ti3O7, where in- situ XAS experiment was carried out to investigate its discharged state (Na4Ti3O7) by measuring the Ti K-edge upon electrochemical cycling. Similarly, the near edge region (XANES) of different nickel ferrite spinels were evaluated to ascertain their oxidation state and local coordination environment before and after redox cycling at high temperature.

41. Role of Electrochemistry in Ferroelectric Hysteresis Joyprokash Chakrabartty, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Federico Rosei) Nano structured ferroelectric (FE) oxides draw attention in science community because of numerous application of its spontaneous reversible polarization in electronic devices. In addition, FEs are earth abundant, easy to synthesis and low degradation of electronic properties while expose to atmosphere. The FEs are characterized by recording traditional hysteresis loops constructed by integrating the current flowing through FEs over time under the application of a varying bias voltage, current which includes polarization switching currents in addition to the linear capacitive and the undesired leakage contributions. Ideal hysteresis loops are symmetric and the remnant polarization and coercive fields are easily extracted from the loops, thus polarization switching is represented in the hysteresis of the current-voltage loop by two symmetric switching peaks. The same switching phenomena can be observed in some non-ferroelectric systems thus complicates the measurements of true responses of FEs. In FE thin films, hysteresis current-voltage loops exhibits switching peaks which do not always confirm the response of ferroelectric polarization rather it may come from due to defects present in the films, film thickness and even types of electrodes. Besides switching peaks, there are other peaks might be appeared in the current-voltage loops which shows confusing behavior to understand the origin. In this work, we will present the dynamics of reversible FE polarization switching of BiFeO3(BFO)/SrRuO3(SRO)/BiMnO3(BMO) heterostructure thin films. All crystalline films are grown on (100) oriented Niobium doped SrTiO3 (NSTO) single crystal substrates by pulsed laser deposition. We will also show how electrochemical reaction affects the remnant polarization of the whole


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device. In addition, we will present the potentiality of the device to act as high density data storage for computer memory applications.

42. Boosting Solar Water Splitting in Plasmonic Photocatalysts Xin Jin, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Luca Razzari) Surface-plasmon-assisted photocatalysis has been extensively investigated in recent years for its promising applications in solar water splitting. A large number of studies focusing on modifying the geometry and size of the plasmonic component in nanohybrids has appeared in the literature. However, the fundamental role played by the resonances that can develop within the semiconducting part of the photocatalysts has been somehow overlooked. In this work, we exploit the properties of 'whispering gallery modes' in properly-engineered nanohybrids to boost the activity of plasmonic photocatalysts.

43. Novel Carbon Dioxide (CO2)-Responsive Fluorescent Hyperbranched Poly(ether amine)s Bing Yu, University of Sherbrooke (Yue Zhao) A series of anthracene-capped hyperbranched poly(ether amine)s (hPEA-AN) with different hydrophilicity were designed and synthesized. Their fluorescence emission intensity in aqueous solution increases after carbon dioxide (CO2) bubbling as a result of the protonation of the tertiary amino groups in the polymer. On one hand, the degree of increase is larger when the polymer is more hydrophobic and the increase upon CO2 bubbling is faster at a lower polymer concentration. On the other hand, the amino groups in the polymer can be partially deprotonated after N2 bubbling, accompanied with a weakening of the fluorescence intensity. However, this process is very slow, which may be ascribed to the diffusion restriction of CO2 molecules out of the core. This mechanism was verified by 1H NMR spectra. This kind of hyperbranched polymer can be potentially used as nanosensor to detect the amount of CO2, which is more stable than tertiary amino group-containing linear polymer, resulting from the slow deprotonation process of hPEA-AN during N2 bubbling.

44. Preparation of Multilayer Nanocomposite Membranes Containing Upconversion and Gold Nanoparticles

Jun Xiang, University of Sherbrooke (Yue Zhao) The integration of upconversion nanoparticles (UCNP) and gold nanoparticles (AuNP) has been an active research topic due to potential applications in bioimaging, sensing, solar cell and detection. However, regulating the interaction between UCNP and AuNP through layer-by-layer (LbL) assembly to control the electronic and optical properties of the resulting materials is rare. In the present study, we prepared nanocomposite membranes comprised of both nanoparticles by means of the LBL method. The arrangement of UCNP and AuNP layers in a spatially controllable fashion led to multilayer films that display different near-infrared (NIR) light-induced photoluminescence as a result of the interaction between the two types of nanoparticles. This study demonstrates an easy way to arrange or organizes UCNP and AuNP into thin films whose upconversion photoluminescence and surface plasmon resonance can be explored.

45. Complex self-assembled films generated by evaporation of aqueous suspensions of cellulose nanocrystal

Xiaoyue Mu, McGill University (Derek G. Gray) Cellulosic liquid crystalline materials, such as cellulose nanocrystals (CNC)[1,2] form chiral nematic phases that show a rich variety of optical textures in the liquid crystalline state. The ordered structures in the liquid crystalline state may be preserved with modification in solid films prepared by simple evaporation of solvent or suspending medium. The films prepared by evaporation of water from aqueous suspensions of CNC, show beautiful patterns when viewed by polarized light microscopy. Many factors govern the formation of these ordered films. These


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include 3-D self-assembly governed by mass transfer in the evaporating droplet[3] and factors such as CNC axial ratio, surface charge and ionic strength of the CNC suspension, which may influence the onset of gelation and glass formation during evaporation.[4] In this poster, we attempt to relate the structures observed in dry films by optical and atomic force microscopy to the self-assembly processes that spontaneously occur during evaporation of CNC suspensions.

1. Revol, J.-F.; Bradford, H.; Giasson, J.; Marchessault, R. H.; Gray, D. G. Helicoidal Self-ordering of Cellulose Microfibrils in Aqueous Suspension. Int. J. Biol. Macromol. 1992, 14, 170-172.

2. Lagerwall, J. P F; Schütz, C.; Salajkova, M.; Noh, J. H.; Park, J. H.; Scalia G.; Bergström, L. Cellulose nanocrystal-based materials: from liquid crystal self-assembly and glass formation to multifunctional thin films. NPG Asia Materials [Online early access]. DOI:10.1038/am.2013.69.

3. Mu, X.; Gray, D. G. Droplets of cellulose nanocrystal suspensions on drying give iridescent 3-D 'coffee-stain' rings. Cellulose 2015, 22(2), 1103-1107.

4. Mu, X.; Gray, D. G. Formation of chiral nematic films from cellulose nanocrystal suspensions is a two-stage process. Langmuir 2014, 30, 9256-9260.

46. Interaction between single strands of siRNA and different chemical groups Lucie Giraud, Université de Montréal (Suzanne Giasson) Gene silencing activity of small interfering RNA (siRNA) has been demonstrated for double and single strands. To overcome environmental degradation and sufficient dose delivery to target cells, actual strategies consist to complex double-stranded siRNA with cationic vectors through electrostatic interactions. Unfortunately cationic vectors are known to cause more toxicity than uncharged ones. Single-stranded siRNA (ss-siRNA) have demonstrated similar therapeutic effects than double-stranded analogues but offer more possibilities of complexation using various interactions. To better understand the fundamental aspect driving the complexation of ss-siRNA with macromolecules or nanovectors, the interactions between flat surfaces of various chemistries across ss-siRNA solutions were quantitatively investigated using the Surface Forces Apparatus. In addition, the complexation of ss-siRNA with liposomes and micelles of different surface charges was conducted. The results show that ss-siRNA can self-assemble onto hydrophilic (positively and negatively charged) and hydrophobic surfaces suggesting that the complexation of siRNA does not only occur through electrostatic interactions but also through hydrophobic interactions and hydrogen bonding. Depending on the nature of interactions, different binding strengths were observed and are correlated with the liposome and micelle loading efficiency. This finding opens up new possibilities for designing nanovectors with controlled interactions and enhanced siRNA complexation efficiency and controlled release.

47. Towards synthesis of high-quality near-infrared emitting PbS quantum dots and their application in solar cells

Rui Zhang, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Federico Rosei) A cation exchange approach is proposed to synthesize monodisperse, stable near-infrared(NIR)-emitting PbS/CdS quantum dots(QDs) with a high QY of 67%. The PbS/CdS QDs with a tunable thicker shell were synthesized via a two-step cation exchange approach, in which the shell thickness of ~0.7 nm is optimal for QDs showing the highest quantum yield and good photostability, with the core size ranging from 2.6 to 5 nm. The PbS/CdS core/shell QDs may have a great potential application in solar cells.

48. Bioinspired mineralization using nanobuilding blocks of trees Amir Sheikhi, McGill University (Theo van de Ven) The quest for designing new nanomaterials to unravel and mimic the biogenic mechanisms behind the formation of superior natural structures through biomineralization has stimulated a broad range of disciplines. Despite the advancement in this field, little effort is devoted to combine nanotechnology


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principles with chemical functionalization to convert inactive green materials to alternative biomimetic motifs. Here, we show that the nanobuilding blocks of trees, comprising cellulose, the most abundant yet inactive biopolymer in the world, can be engineered to yield a new class of nanocelluloses with a ppm-level biomimetic effect.

49. TiO2-Carbon Nanohybrid Photocatalysts for Efficient Water Purification Jianming Zhang, Université du Québec à Montréal (Jérôme Claverie) Nanocomposites composed of TiO2 and carbon materials (C) are widely popular photocatalysts because they combine the advantages of TiO2 to the enhanced charge carrier separation and lower charge transfer resistance brought by C. However, the presence of carbon can also be detrimental to the photocatalytic performance as it can block the passage of light and prevent the reactant from accessing the TiO2 surface. Here using a novel interfacial in situ polymer encapsulation-graphitization method, where a glucose-containing polymer was grown directly on the surface of the TiO2, we have prepared uniform TiO2@C core-shell structures. The thickness of the carbon shell can be precisely and easily tuned by simply programming the polymer growth on TiO2. The resulting core@shell TiO2@C nanostructures possess the highest activity for the photodegradation of organic compounds, when the carbon shell thickness is 1-2 nm. Also, using similar technique, we have developed a polymer micelle method to synthesis carbon quantum dots (CQDs). This preparation method renders the mass production of multifunctional CQDs possible. The CQDs were assembled with TiO2 into a TiO2-CQDs hybrids for photocatalytic water purification.

50. Detection of TNT and RDX by surface plasmon resonance and surface-enhanced Raman spectroscopy based on gold nanoparticles molecular imprinted matrix

Geneviève Granger, Université de Montréal (Jean-François Masson) Over the last few years, energetic materials such as 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) have shown an environmental impact on military bases, the surrounding population, fauna and flora, caused by military training involving ammunitions. On shooting ranges, soils near the firing positions and around targets require special monitoring, since the quantities of explosives residues found are significant, and these compounds can be transported to surface water and groundwater by percolation. However, the current procedure to detect energetic materials in natural water is complex, long and poorly adapted. These operations require highly specialized personnel and increase the risk of cross contamination. Therefore, it is difficult to ensure a fast and continuous monitoring of the contaminants. The current objective is to develop a technique for identifying and quantifying explosives and their degradation products in natural water. Also, this test has to be in-situ, inexpensive and fast. Surface plasmon resonance (SPR) and surface-enhanced Raman spectroscopy (SERS) have been extensively used to probe energetic materials. A bis-aniline-cross-linked gold nanoparticles (AuNPs) matrix is used as a molecular imprinted polymer (MIP) on gold film to selectively capture the target compound. The association of the target such as TNT or RDX to the MIP with π-donor-acceptor interactions have allowed the detection of explosives by following SPR refractive changes. Plasmon coupling effects between the AuNPs and the gold film could also increase the SPR and SERS signals. The utilisation of MIP based essay will provide a tool for the extraction and pre-concentration of TNT or RDX on the detector's surface and will allow the detection of lower concentrations in natural water.

51. Dynamic-SERS Optophysiology: A nanosensor for monitoring cell secretion events Felix Lussier, Université de Montréal (Jean-François Masson) Signaling mechanisms between multiple living cells are governed with the secretion of small molecules. During these secretion events, the concentration of these chemical messengers can be elevated, albeit still at low concentration, for a short period of time requiring highly sensitive sensors. The characterisation of these


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chemical messengers and the evaluation of their respective concentration contain important information about living cells, which hold a promising use in medical diagnostic and in biological sciences. The conventional analytical tools are typically not suited for measuring the fast and heterogeneous changes in concentration during the secretion events. In one example of success, micro and nanometric sized electrodes have been extensively used for local in vivo electrochemical sensing. Yet, electrochemistry is still mainly limited to electroactive molecules, and offers lower sensitivity for a broader range of relevant biochemical targets. Alternatively, plasmonic nanomaterials lead to enhanced spectroscopy such as surface enhanced Raman spectroscopy (SERS), which allows both identification of the analyte while allowing detection at single molecule level. To address these current limitations, we developed a plasmonic nanopipette based on a nanometric glass patch clamp pipette, which were recently applied as nanoprobes to locally and selectively monitor cellular secretion nearby a single or a group of living cells. The nanoprobe were generated by adsorption of gold nanoraspberries onto an APTES-functionalized nanopipette and were intensively characterized and showed sensitivity at single molecule level by dynamic SERS (D-SERS). Furthermore, in order to analyze the complex and heterogeneous SERS response in vivo, we generated a SERS spectral database of multiple relevant metabolites (e.g. ATP, lactate and pyruvate) to allow a characterization of the cellular secretions. Based on this database, we developed a chemiometric approach capable of sorting and counting metabolites by comparing each experimental spectrum to the different standards. With these novel tools, a local, multiplexed sorting and counting of lactate, pyruvate, ATP and urea were achieved in realistic conditions near MDCKII cells line by D-SERS. Spontaneous release of metabolites was also monitored following the injection of detergent in the medium. Selectivity and sensitivity of both, the nanosensor and chemometrics data processing will be discussed and biological results will be presented.

52. Development and design of polymeric nanomaterials with multifunctional applications Soyoung An, Concordia University (John Oh) Our research group is interested in the construction of advanced polymeric nanomaterials as multifunctional drug delivery nano-devices, cellular imaging platforms and tissue scaffolds for biomedical application. We have integrated stimuli-responsive degradation (SRD) functionality in the development of polymer-based multifunctional nanomaterials. Such nanomaterials are designed to be degraded upon the cleavage of dynamic linkages in response to single or multi-stimuli. Of particular interest is the use of dynamic disulfide chemistry to develop stimuli-responsive degradable nanomaterials in which can tune lower critical solution temperature, control nanoparticle morphologies and enhance controlled drug release. Currently, our group focuses on development of SRD-based nanometerials such as self-assembled block copolymer-based nanocarriers, hydro(nano)gels, fibers, thermoresponsive polymers and as well as functionalized carbon-based materials. Further, we are exploring a new concept to design and develop high-performance crosslinked materials with self-healing ability for industrial application.

53. Synergy of Two Assembly Languages in DNA Nanostructures: Self-Assembly of Sequence-Defined Polymers on DNA Cages

Pongphak Chidchob, McGill University (Hanadi Sleiman) DNA base-pairing is the central interaction in DNA assembly. However, this simple four-letter (A-T and G-C) language makes it difficult to create complex structures without using a large number of DNA strands of different sequences. Inspired by protein folding, we introduce hydrophobic interactions to expand the assembly language of DNA nanotechnology. To achieve this, DNA cages of different geometries are combined with sequence-defined polymers containing long alkyl and oligoethylene glycol repeat units. Anisotropic decoration of hydrophobic polymers on one face of the cage leads to hydrophobically driven formation of quantized aggregates of DNA cages, where polymer length determines the cage aggregation number. Hydrophobic chains decorated on both faces of the cage can undergo an intrascaffold 'handshake' to generate


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DNA-micelle cages, which have increased structural stability and assembly cooperativity, and can encapsulate small molecules. The polymer sequence order can control the interaction between hydrophobic blocks, leading to unprecedented 'doughnut-shaped' DNA cage-ring structures. We thus demonstrate that new structural and functional modes in DNA nanostructures can emerge from the synergy of two interactions, providing an attractive approach to develop protein-inspired assembly modules in DNA nanotechnology.

54. Solution-phase nano-scale plasmon coupling of gold nanoparticle rings scaffolded on Tobacco Mosaic Virus capsid protein

Dan Petrescu, McGill University (Amy Blum) Nanophotonic metamaterials can be designed to manipulate electromagnetic waves with applications spanning nanophotonic circuitry, photovoltaics, tumor therapy, and signal detection enhancement in analytical techniques. Previous work has predicted that plasmonically coupled noble metal nanoparticles arranged in a ring would exhibit a strong magnetic dipolar response along with a negative index of refraction. Fabrication of nanomaterials with such precise geometries and arrangements, however, remains limited by the current resolution of top-down lithographic techniques. To achieve higher precision and reproducibility of nanostructure placement, bottom-up bio-molecular self-assembly techniques present an appealing alternative. By harnessing the diverse chemical functionality and self-assembling properties of biomacromolecular systems such as proteins, it becomes possible to chemically fabricate dynamic solution-phase nanophotonic metamaterials whose optical properties can be controlled in vitro by parameters such as ionic strength, pH, and temperature. Our studies explore the Tobacco Mosaic Virus (TMV) capsid protein, a structure displaying disk-like self-assembling capabilities, as a scaffold for generating rings of gold nanoparticles on the faces or edges of this supramolecular structure. A mutated TMV protein, S123C, which predominantly favored this disk phase, was found to bind nanoparticles non-covalently through charged surface residues on the face of the disk, as evidenced by TEM micrographs. Temperature and pH provided a way to physico-chemically tune the number of particles on the rings. Further mutation of this protein solvent-exposed the hitherto obstructed N-terminus, thereby affording a chemical handle on which to covalently bind nanoparticles. Bio-conjugation of a fluorophore allowed for spectroscopic quantification and confirmed increased tagging efficiency for this mutant along with selective conjugation of the N-terminus. Lipoic acid was immobilized at the N-terminus in this manner and covalently bound gold at the edge of the disk, thus providing a way to vary the ring diameter and robustness. UV/vis absorbance and dark-field scattering data confirm nano-scale plasmon coupling between particles.

55. Synthèse d'une spinelle fonctionnalisée avec de la silice mésoporeuse et des nanoparticules d'or

Laura Paradis Fortin, Université de Sherbrooke Améliorer les propriétés d'un matériau pour des applications futures en catalyse hétérogène La structure existante consiste d'un cœur de Fe3O4 enrobé de silice dense avec à sa surfaces des NPs d'or colloïdales (10nm) et finalement recouvert d'une couche de silice mésoporeuse. Le Fe3O4 est utilisé pour ses propriétés magnétiques tandis que la silice est utilisé pour faciliter le greffage de l'or ainsi que de protégé de la désactivation. L'or est utilisé puisque c'est un matériau actif catalytiquement. Le améliorations que j'apporte sont de faire une première couche de silice mésoporeuse et ensuite faire la synthèse in-situ des nanoparticules d'or à l'intérieur des pores. De cette façon, on augmente le loading total de l'or, les NPs d'or sont de tailles plus petites (2nm) car leur croissance est bloquée par la taille des pores et le frittage est aussi bloqué physiquement par les pores.


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56. Towards Controlling the Growth and Chirality of Silica-Carbonate Microstructures in Inorganic Systems

Alicia McTaggart, Concordia University (Louis Cuccia) The importance of chirality and chiral materials is widespread in the pharmaceutical industry and the optical functional materials industry. One only has to look to nature to find examples of homochirality; at the molecular level, examples include sugars and amino acids,. Moreover, the interaction between the organic and inorganic components of biological systems leads to some of the most beautiful (and often chiral) patterns seen in nature, as is demonstrated by the shell of snails and the chiral narwhal tusk. However, the pH-dependant coprecipitation reaction of barium carbonate with sodium silicate, under the influence of atmospheric CO2, suggests that this phenomenon is not the exclusive domain of biomineralisation processes. In such reactions, the formation of spirals is only one of the types of structures that are biomimetic in appearance. The objective of our research is to explore how the growth and evolution of silica-carbonate microstructures can be controlled by carrying out phase one reactions under varying experimental conditions of pH and CO2 concentration. Towards this end, it was established by light microscopy and scanning electron microscopy (SEM) that stems, vases and corals form at pH 11.8, in contrast to spirals and leaves at pH 11.2. In phase two, the chiral aspects of the spirals formed at pH 11.2 were assessed. Since it was discovered that the chirality of the spiral growth showed a stochastic distribution (125 clockwise : 123 counter-clockwise), the next aim is to explore the possibility of guiding the spirals towards a specific chirality by incorporating chiral additives in the crystallisation reactions. Ultimately, it is the hope that this research will foster a better understanding of not only chirality in biomineralisation processes, but also those concerning building functional materials via a bottom-up approach.

57. Effect of Ceramide-C16 on the polymorphic behavior of phospholipid bilayers Mahmoudreza Doroudgar, Université de Montréal (Michel Lafleur) Ceramide-C16 (Cer-C16) is a lipid that is associated with several serious diseases like diabetes, obesity, Parkinson, and certain types of cancers. Many research efforts are devoted to identify the role of Cer-C16 in modifying the behavior of lipid membranes and to understand how it is involved in diseases. Currently, most of the research efforts examine the effects of this lipid on the lateral distribution/phase separation in membranes. In this project, we investigated the impacts of Cer-C16 on the lipid polymorphism, a property that also modulates the cell membrane behavior. We characterized the phase behavior of various Cer-C16 / 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) bilayers, using differential scanning calorimetry (DSC), 2H and 31P solid-state NMR spectroscopy. The results revealed that presence of only 5 mol% Cer-C16 upshifts the temperature of the gel-to-liquid crystalline (Lβ-Lα) phase transition, and downshifts the temperature of the liquid crystalline-to-inverted hexagonal (Lα-HII) phase transition of the bilayers. In addition, Cer-C16 broadens significantly both phase transitions. These impacts are associated with the small polar head group of Cer-C16. The capability of Cer-C16 to perturb the membrane fluidity and its propensity to adopt HII phase may affect the proper functionality of cell membranes.

58. Poly(N-isopropylacrylamide) microgels as aqueous lubricants Pierre Vialar, Université de Montréal (Suzanne Giasson) Poly(N-isopropylacrylamide) (pNIPAM) is the most extensively studied responsive hydrogel, due to its Low Critical Solution Temperature (LCST) of 32 °C in water, biocompatibility and flexibility towards chemical modification leading to responsiveness to a large range of stimuli. In this study, we aim at synthesizing charged pNIPAM nanoparticles - also known as microgels - for physical adsorption and chemical grafting on mica substrates in order to perform nanotribology experiments using a Surface Force Apparatus. The particles undergo reversible shrinking/swelling as a response to thermal stimuli, the swollen diameter is ca 100 nm with a narrow size distribution. Two synthesis routes have been followed: the first leading to primary


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amine-bearing particles - thus positively charged - crosslinked with N,N'-Methylenebisacrylamide (MBA), which was previously reported. The second approach uses a polymer-to-polymer crosslinking between amine sites and dicarboxylicacids, and the particle size is controlled by the concentration of hydrophobic anion tetraphenylborate - leading to negatively charged particles. Both systems have been characterized using dynamic light scattering, atomic force microscopy and zeta potential measurements.

59. Applications biologiques et pharmacologiques de la spectroscopie RMN des solides et autres techniques spectroscopiques

Justine Dionne, Université Laval (Michèle Auger) L'objectif principal du programme de recherche du groupe de la professeure Michèle Auger est l'étude de la structure, des propriétés d'auto-assemblage et du mécanisme d'action de peptides antimicrobiens, de peptides amyloïdes et de la soie d'araignée. Ces systèmes sont étudiés par une combinaison de plusieurs techniques spectroscopiques, notamment les spectroscopies RMN des solides et en solution, infrarouge, Raman, de dichroïsme circulaire et de fluorescence. Notre groupe s'intéresse à l'étude de peptides antimicrobiens cationiques qui sont des effecteurs de la réponse immunitaire non spécifique. Nos études se portent sur la caractérisation de la structure et des interactions membranaires d'un peptide synthétique 14-mère et d'un peptide antimicrobien naturel, la thanatine. Notre groupe s'intéresse aussi à l'étude de peptides amyloïdes, en particulier à un peptide de 12 acides aminés dérivé de l'alpha-synucléine, une protéine impliquée dans la maladie de Parkinson. Un autre aspect de notre programme de recherche porte sur l'étude de protéines de soie d'araignée. Nous nous intéressons entre autres à quantifier le changement de conformation, d'orientation et de mobilité des chaînes polypeptidiques du fil de survie induit par la supercontraction. De plus, notre groupe s'intéresse à l'étude de fibres provenant de différentes espèces d'araignée et à l'étude de protéines de soie recombinantes en solution. Finalement, des projets collaboratifs impliquent l'étude de la recoverine, une neuroprotéine impliquée dans le cycle de phototransduction visuel, la diffusion de drogues à travers la peau et la caractérisation de phospholipides fluorés.

60. Reversing the chirality of cellulose nanocrystals Kevin Conley, McGill University (Theo van de Ven) Chirality exists throughout cellulosic materials but it is unclear why chirality develops and how it propagates throughout the different length scales. Twists are observed in the trunks of trees, micron-sized fibers, and nanometer-sized cellulose nanocrystals. The individual building block of cellulose is chiral, but that does not explain how the chirality of the molecule relates to chirality at different lengths. Twisting of cellulose nanocrystals about the crystal axis would explain how the colloidal particles self-assemble into chiral nematic liquid crystals, and lead to potential products such as a support for chiral catalysis. Calculating the structure of cellulose nanocrystals show that rather than being flat rod-like particles, the minimum energy conformation of cellulose nanocrystals is twisted with a frequency and handedness which depends on the crystal width. Larger crystals have a right-handed twist, but as the crystals become thinner the handedness reverses. Optically inactive cellulose binding dyes probe structural chirality of cellulose nanocrystals surface using induced circular dichroism and show the reversal of handedness as the crystals are thinned.

61. Flow alignment of Acidic Collagen Solutions Oscar Aguilar Gutierrez, McGill University (Alejandro Rey) The dynamic behaviour of collagen solutions is of great interest for tissue engineering purposes and is widely used in non-equilibrium self-assembly processes to create the so-called biological plywoods. These processes make use of coating flows of biopolymer solutions where the macromolecules are submitted to shear and


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extensional deformations to dynamically align the respective building block for later evaporation processes to create the aforementioned materials. This work focuses on the alignment of collagen acidic solutions, precursors of defect-free collagen films, through the modelling, analysis and simulation of the evolution of the microstructure of the solution when submitted to a simple shear flow between parallel plates based on liquid crystalline physics. An analysis of the model allows to estimate crucial physical parameters from experimental data to be used in the simulations as inputs to obtain material function predictions for high shear rate regimes, where flow instabilities may appear in certain flow configurations.

62. Self-assembled monolayers of ferrocenyldodecanethiolate as tools to monitor the ion-pairing behavior and the micelle formation of anionic amphiphiles

Eric Dionne, Université de Montréal (Antonella Badia) One of our research axes is to study the redox adsorption (i.e. ion-pairing) of negatively charged ions with the oxidized ferrocene moieties of ferrocenyldodecanethiolate (FcC12SAu) self-assembled monolayers (SAMs). The pairing of small inorganic anions (i.e. PF6-, ClO4- or BF4-) has been extensively documented. We have exploited this phenomenon for the redox actuation of microcantilevers.[1]) We also focused our work on the pairing of non-traditional electrolyte anions such as anionic amphiphiles to oxidized FcC12SAu SAMs. [2-4] Amphiphiles are molecules that possess a polar head group attached to a hydrophobic alkyl chain. At a certain concentration, amphiphiles can self-aggregate into micelles. These micro-structures exist in an equilibrium state with monomers (i.e., non-aggregated amphiphiles) at the critical micellar concentration (cmc). Below the cmc, only monomers exist in solution. We started by using n-alkyl sulfates (with n = 6, 8, 10 and 12) and have discovered that the Faradaic electrochemistry at the SAM interface is radically different from what is obtained in solutions containing small inorganic anions. For instance, a break, in plot of the E°'SAM vs. the logarithm of the anionic amphiphile concentration, is visible at the cmc.[4]. This break was exploited to determine the cmc of other anionic amphiphiles (sodium n-hexyl sulfonate, sodium diamyl sulfosuccinate, sodium dodecanoate) but also the mixed cmc of binary mixtures of sodium hexyl sulfate and sodium dodecyl sulfate. [5] This poster will discuss these new insights and the fact that the ferrocenyldodecanethiolate SAMs are an effective redox platform for sensing anionic amphiphile behavior in aqueous solutions.

1. Dionne, E.R., Toader, V., Badia, A., Langmuir 2014, 30, 742. 2. Norman, L.L., Badia, A., Langmuir 2007, 23, 10198. 3. Nguyen, K.-L., Dionne, E.R., Badia, A., Langmuir 2015, 31, 6385. 4. Dionne, E.R., Sultana, T., Norman, L. L., Toader, V., Badia, A., J. Am. Chem. Soc. 2013, 135, 17457. 5. Dionne, E.R., Badia, A., ACS Appl. Mater. Interfaces 2016 (Manuscript under modification).

63. DNA-templated synthesis of sequence-controlled RNA amphiphiles using a combination of enzymatic and automated solid-phase methods

Michael Dore, McGill University (Hanadi Sleiman) Functional polymers in nature, in particular nucleic acids and enzymatic proteins, draw their utility from two primary attributes: information storage and self-assembly. Synthetic molecules that combine these two characteristics have the potential to allow the bottom up design of functional soft-materials. Nucleic acid based amphiphiles are an example of such molecules - DNA or RNA afford information storage and addressability, while hydrophobicity directs higher-order self-assembly. Despite challenges on account of the disparity between the solubilities of the separate components, a synthetic strategy for the aqueous-phase fabrication of RNA amphiphiles has been demonstrated. Monodisperse DNA-amphiphiles were utilised as supramolecular templates to position and facilitate the copper-free click-conjugation of enzymatically-produced RNA to hydrophobic molecules. Initially a self-templated reaction was performed, in which a short segment of RNA was conjugated to the hydrophobic terminal of a complementary DNA amphiphile, to yield a DNA-RNA hybrid amphiphile. Subsequently, pre-assembled DNA micelles were used to template the conjugation of enzymatically produced


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RNA to phosphate-linked hexaethylene alkyl chains. RNA annealed to the complementary DNA corona, while the hydrophobic HE6 molecules were encapsulated within the micelle core, facilitating the conjugation. Greater than 60% yield was achieved, and conjugated product was undetectable in aqueous solution lacking the presence of the micelles.

64. Hydrogen Bond Stabilized Nanoparticle-Liquid Crystal Composites Mahdi Roohnikan, McGill University (Linda Reven) We report here the development of stable nanoparticle-liquid crystal composites based on hydrogen bonding. The ligand shells of zirconia nanoparticles (ZrO2 NPs) were varied to control their interaction with 4-n-hexylbenzoic acid (6BA), a simple hydrogen bonded nematic liquid crystal. Non-functionalized ZrO2 NPs and ZrO2 NPs functionalized with carboxylic and benzoic acid pendant groups were dispersed in 6BA. Luminescent Tb3+-doped ZrO2 NPs were also prepared. The miscibility and effect of the NPs on the nematic order as a function of particle concentration was characterized by polarizing optical microscopy (POM), fluorescence microscopy and 2H NMR. The non-functionalized ZrO2 NPs have the strongest effect on the LC matrix, lowering the orientational order parameter and phase transition temperatures, and aggregating in the nematic phase above 0.1 wt% ZrO2. The strong perturbation of the LC order is due to an irreversible binding of 6BA to the ZrO2 surface via a zirconium carboxylate bond. ZrO2 NPs functionalized with mixed monolayers of hexylphosphonic acid and the diacid, HO2C(CH2)6PO3H2, which selectively bind via the phosphonic acid groups, are miscible up to 3.0 wt% ZrO2 and cause only a slight lowering of the 6BA orientational order. The higher stability of the dispersions of the functionalized ZrO2 NPs in nematic 6BA is attributed to reversible NP-LC hydrogen bonding interactions.

65. Dynamic control over supramolecular handedness by selecting chiral induction pathways at the solution-solid interface

Yuan Fang, McGill University (Dima Perepichka) A dominant theme within the research on two-dimensional (2D) chirality is the sergeant-soldiers principle, where a small fraction of chiral molecules is used to skew the handedness of achiral molecules to generate a homochiral surface. Here we present an eloquent combination of sergeant-soldiers principle and temperature-dependent molecular self-assembly to unravel a unique chiral amplification mechanism at the solution-solid interface. We demonstrate that, depending on the concentration of a sergeant-soldiers solution, the majority handedness of the system can be amplified or entirely reversed after an annealing step furnishing a homochiral surface. Two discrete pathways that affect different stages of 2D crystal growth are invoked for rationalizing this phenomenon. We present a unique set of experiments where the access to each pathway can be precisely controlled. Our results demonstrate that a detailed understanding of subtle intermolecular and interfacial interactions can be used to induce drastic changes in the handedness of a supramolecular network.

66. Exploiting Conjugated Polyelectrolyte Photophysics toward Monitoring Real-Time Lipid Membrane-Surface Interaction Dynamics at the Single-Particle Level

Christina Calver, McGill University (Gonzalo Cosa) The interaction of conjugated polyelectrolytes (CPEs) with lipid membranes leads to dramatic changes in their photophysical properties.[1,2] The changes resulting from the insertion of CPEs within membranes include spectral shifts (aggregate to single-chain emission), emission enhancement, and poor exciton transport. In this presentation we show how these unique photophysical properties of CPEs can be exploited to observe membrane dynamics.[3] We report the real-time observation of the interaction between cationic liposomes and a charged scaffolding formed by the deposition of the conjugated polyanion onto 100 nm diameter SiO2 nanoparticles (NPs). The interaction of the liposomes with the CPE promoted deaggregation of


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the polymer and led to large emission enhancements. Single-particle fluorescence studies exploited this phenomenon as a way to monitor the deformation of individual liposomes on surface-immobilized NPs. Cryo-TEM experiments complemented these results by yielding a structural view of the process. We foresee that the single-particle studies we report in this work may be readily extended to study membrane dynamics of other lipids including cellular membranes, where the ability to adjust topology in response to cues from charged biopolymer scaffoldings is essential to many cellular activities.[4]

1. Karam, P.; Ngo, A.T.; Rouiller, I.; Cosa, G. Proc. Natl. Acad. Sci. U. S. A. 2010, 107, 17480-17485. 2. Karam, P.; Hariri, A.A.; Calver, C.F.; Zhao, X.; Schanze, K.S.; Cosa, G. Langmuir 2014, 30, 10704-10711. 3. Calver, C.F.; Liu, H.-W.; Cosa, G. Langmuir, Articles ASAP. 4. McMahon, H.T.; Gallop, J.L. Nature 2005, 438, 590-596.

67. Laboratoire des polymères électroactifs et photoactifs Pierre-Olivier Morin, Université Laval (Mario Leclerc) Notre groupe de recherche s'intéresse au design, à la synthèse et à la caractérisation de polymères conjugués pour des applications dans le domaine de l'électronique organique. Nous cherchons à développer des polymères pour la fabrication de dispositifs comme les transistors organiques à effet de champ, les cellules photovoltaïques et les biosensors.

68. Sizes of silica fillers and their influence on composite mechanical and optical properties Eric Habib, Université de Montréal (Julian Zhu) Dental resin composites represent an important family of materials that have been evolving in response to the needs in biocompatibility and mechanical properties. These are composite materials consisting of mostly inorganic fillers and additives bound together with a polymer matrix. Many fillers have been studied, but the largest body of research remains proprietary in the industrial sector. This work examines the effect of different sizes of silica particles on the mechanical and optical properties of the end composite materials. The Stöber method was used to synthesize several sizes of silica particles that were then surface functionalized using γ-methacryloyl trimethoxysilane. Particles of 70, 100, 125, and 500 nm were tested in addition to polydisperse commercial macro-silica (0.5-10 µm). The particles were characterized by dynamic light scattering and scanning electron microscopy. These particles were then fully integrated with the commercial monomers bisphenol A glycerolate dimethacrylate and triethyleneglycol dimethacrylate using a three roll mill to obtain the final composite pastes. These were then photopolymerized using a dental lamp, and mechanical testing was performed, measuring flexural strength and modulus. Optical testing was performed by measuring the transmittance and reflectance of the samples. Finally, depth of cure was evaluated by measuring the degree of conversion of the samples at different depths using Raman spectroscopy. The composites yielding the best mechanical properties were shown to be the 500 nm silica particles, owing to their higher possible loading (70% vs 60% for the smallest silica). These materials, however, had low transparency, which lead to the inadequate depth of cure of 3 mm for one minute of curing. The optical properties were most favorable with the smallest particles, showing materials that were almost fully transparent, and showed the greatest depth of cure at 6 mm. Therefore while the nanometer silica showed inferior mechanical properties, the impressive increase in depth of cure proved to be a very useful counterpoint.

69. Mixed Solvent Induced Morphology Evolution in Dip-Coated PS-P4VP Thin Films Hu Zhu, Université de Montréal (C. Geraldine Bazuin) Polystyrene-b-poly(4-vinylpyridine) (PS-P4VP) thin films were dip-coated from mixed-solvent solutions of methanol and THF where the methanol/THF ratio was varied systematically. The selectivity of methanol for P4VP and of THF for PS induces a morphology evolution in the thin films. The evolution was associated with a


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phase inversion from P4VP nanostructures (dots, cylinders) in a PS matrix using pure THF to PS nanostructures (cylinders, dots) in a P4VP matrix in methanol-rich solutions.

70. Azobenzene-modified Silk Gels for Light-Induced Surface Patterning Michael Landry, McGill University (Christopher Barrett) Silk fibroin from Bombyx mori silkworms is used in diverse applications in materials science due to its rich polymer chemistry. Although silk can be processed into various material classes that are suitable for biological material applications, such as tissue engineering, further enhancement of its properties can be achieved through chemical modifications of the amino acid side chains - such as tyrosine. One method to retain the biocompatibility of silk, while enhancing its optical properties is functionalization with azobenzene, yielding a material called azosilk. By utilizing a confocal microscope, we were able to irradiate the surface of the hydrated gels, yielding fluorescent surface patterns under 800 nm (two-photon) irradiation. The written patterns can be easily visualized by observing the fluorescence emitted at 550 nm, excited by 800 nm. In this microlithographic process, out-of-plane expansion of the film causes micrometre-sized blisters to form on the surface. Micro-blisters were characterized using AFM, and exhibited a 10-fold decrease in modulus (photo-softening). The induced radius of curvature associated with blister formation, together with photo-softening are expected to be valuable material characteristics for guided cell growth.

71. Nanomaterials for Energy Conversion and Storage Xiaohua Yang, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Shuhui Sun) In this poster presentation, I will briefly introduce the research activities and ongoing projects being conducted in Prof. Shuhui Sun's group (Sustainable Nanotechnology (SUN) Laboratory) at INRS-EMT. The SUN group is working on (i) the fabrication of advanced functional nanomaterials (Graphene, doped-graphene, CNTs, doped-CNTs, metal and metal oxide nanostructures, and nanocomposites) from single atoms to nanoparticles, nanowires, nanotubes, and films; (ii) Clean energy conversion and storage, including proton exchange membrane fuel cells (PEMFC) (Low-Pt and Non-Pt catalysts), supercapacitors, lithium batteries, and sodium batteries; (iii) Environmental applications, such as electro-Fenton process for wastewater treatment.

72. Does iron matter the stability of the Fe/N/C non-precious metal catalysts? Gaixia Zhang, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Shuhui Sun) Recently, Fe/N/C catalysts, especially the MOF-based one, have been reported to be one of the most active non-precious metal catalysts for oxygen reduction in PEM fuel cells, with power density levels to that of commercial Pt/C catalyst. However, the long-term stability of Fe/N/C catalyst is still insufficient, which remains the last obstacle to overcome for its practical application in fuel cells. Very recently, through a systematic study, we conclude that neither Fe nor H2O2 alone are responsible for the first rapid decay of MOF-based Fe/N/C catalyst. It is proposed that the micro-pore flooding is at the origin of the first quick decay of Fe/N/C catalyst.

73. Graphene supported Fe3O4 nanoparticles as efficient electrocatalysts for H2O2 production in wastewater treatment

Qiliang Wei, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Shuhui Sun) Magnetic nanoparticles are being studied and developed for various technological applications including biomedicine, bioengineering and electrochemistry. Here, we reported the graphene-supported magnetic Fe3O4 nanoparticles (Fe3O4/GP) as efficient cathode catalyst for H2O2 production in wastewater treatment, through the 2-electron (2e) oxygen reduction reaction (ORR) process. The catalysts were synthesized by a simple precipitation method using NaBH4 as reducing agent to favor the formation of the magnetite phase.


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TEM images indicate the uniform dispersion of Fe3O4 nanoparticles (NPs) on the high surface graphene sheets. In studying the effects of the carbon support on the Fe3O4 NPs for the ORR, we found that Fe3O4/GP shows a more positive onset potential and higher current density, for the ORR in alkaline media than Fe3O4 NPs supported on Printex carbon, highlighting the importance of high surface area of the GP support for improving the ORR performance. The addition of Fe3O4 on carbon supports (both graphene and Printex carbon) increased the %H2O2 to above 60%. Furthermore, both Fe3O4/GP and Fe3O4/Printex catalysts show excellent durability.

74. Atomistic Modeling of Structure II Gas Hydrate Mechanics: Compressibility and Equations of State

Thomas Vlasic, McGill University (Alejandro Rey) Gas hydrates are crystalline solids that consist of small gas molecules trapped within a network of hydrogen-bonded water molecules that form cage-like structures. They are most notably known as an immense potential source of energy, as many natural gas hydrate deposits have been discovered all over the world in the ocean floor as well as in the permafrost. However, gas hydrates are significant in many other areas such as flow assurance, CO2 sequestration, and natural gas transportation and storage. Although research into gas hydrates has been ongoing for the past several decades, their material properties are not well characterized and our understanding of these unique structures at a fundamental level is still lacking. Therefore, this work involves the use of density functional theory to determine the mechanical properties of structure II gas hydrates, and study this structure at the atomistic scale.

75. One-Pot Electrochemical Exfoliation and Functionalization of Graphene Sheets Diby Benjamin Ossonon, Université du Québec à Montréal (Daniel Bélanger) Graphene sheets were spontaneously functionalized with anthraquinone molecules in a one-pot process, during the oxidative electrochemical exfoliation of graphite in a 0.1 M H2SO4 solution containing in-situ generated anthraquinone diazonium ions. This counterintuitive process, involves the electrochemical oxidation of graphite and the reduction of diazonium ions, and occurs by spontaneous reaction of freshly generated graphene sheets with diazonium ions. The grafting yield of this one-pot process is higher than that of a two-step procedure based on the functionalization of already produced graphene sheets. The presence of anthraquinone molecules was confirmed by Fourier transform infrared spectroscopy, electron microscopy, X-ray photoelectron spectroscopy and cyclic voltammetry. Thermogravimetric analysis, Raman spectroscopy and electronic conductivity measurements are consistent with the covalent bonding of anthraquinone of the graphene sheets. Thermogravimetric analysis and cyclic voltammetry data allowed the evaluation of the loading of anthraquinone groups on the graphene sheets.

76. A minimalist approach to complexity: templating the assembly of DNA tile structures with sequentially grown input strands

Kai Lin Lau, McGill University (Hanadi F. Sleiman) Given its highly predictable self-assembly properties, DNA has proven to be an excellent template towards the design of functional materials. Prominent examples include the remarkable complexity provided by DNA origami and single-stranded tile (SST) assemblies, which require hundreds of unique component strands. However, in many cases, the majority of the DNA assembly is purely structural, and only a small 'working area' needs to be aperiodic. On the other hand, extended lattices formed by DNA tile motifs require only a few strands; but they suffer from lack of size control and limited periodic patterning. To overcome these limitations, we adopt a templation strategy, where an input strand of DNA dictates the size and patterning of resultant DNA tile structures. To prepare these templating input strands, a sequential growth technique developed in our lab is used, whereby extended DNA strands of defined sequence and length may be


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generated simply by controlling their order of addition. With these, we demonstrate the periodic patterning of size-controlled double-crossover (DX) and triple-crossover (TX) tile structures, as well as intentionally designed aperiodicity of a DX tile structure. As such, we are able to prepare size-controlled DNA structures featuring aperiodicity only where necessary with exceptional economy and efficiency.

77. Enantiomer-specific oriented attachment of guanidine carbonate crystals Reajean Sivakumar, Concordia University (Louis Cuccia) Enantiomer-specific oriented attachment, an essential process in Viedma ripening, was also investigated in guanidine carbonate crystals. Simply boiling or shaking powdered racemic guanidine carbonate in saturated solution leads to the formation of large crystalline clusters. These clusters, characterized by solid-state circular dichroism and X-ray powder diffraction, were found to be nearly homochiral. This is only the second example of enantiomer-specific oriented attachment and can be thought of as a mesoscale analogue of conglomerate crystallization.

78. Early detection of anti-asparaginase to significantly increase remission rate in acute lymphoblastic leukemia therapy

Alexandra Aubé, Université de Montréal (Jean-François Masson) Leukemia is a blood cancer affecting children with almost 50% of mortality rate. Multiple chemotherapeutic agents are currently used in treatment of leukemia in children and many treatment schedules include asparaginase, a common and very effective therapeutic agent against this illness. Asparaginase treatments suffer from allergic reactions in 30% of the patients which decrease its efficiency and can weaken the patient or lead to anaphylactic shocks in some cases. Since the symptoms of the allergic reaction appear many days after the actual antibody production or never appear at all (silent hypersensitivity), it is of great interest to develop an assay that can allow rapid and simple anti-asparaginase sensing to adjust the treatment during the first days of treatment. To address this issue, we have developed a surface plasmon resonance (SPR) sensor to measure antibodies expressed in leukemic patients in response to asparaginase treatment. SPR sensing is a spectroscopic technique that allows real-time monitoring of specific molecules in complex matrix, when appropriate surface chemistry protects the sensor. In this study, asparaginase acts as the receptor to capture anti-asparaginase to create the biosensor. Different forms of this receptor were investigated with the aim of achieving the highest sensitivity in complex matrix such as serum. Detection was performed in crude human serum to ensure rapid transfer of the method to real clinical samples. The results have shown that anti-asparaginase can be detected in the low nanomolar range in an undiluted human serum using this simple SPR biosensor. Finally, serum samples from a local children's hospital handling most cases of leukemia in the greater Montreal were collected and analyzed. By combining this approach with a peptide surface chemistry developed in our group to reduce non-specific binding, a novel and very effective assay was developed and can easily be adapted to clinical samples.

79. Silver Nanoparticles Ensembles: TEM-Dark Field Correlated Study Serene Bayram, McGill University (Amy Blum) The controlled organization of plasmonic nanoparticles into highly anisotropic 1D arrays and networks offer a platform to attune the flux of surface plasmons. Extended planar nanoparticle assemblies are capable of subwavelength optical guiding, which can result in the miniaturization of integrated optical, photonic and biosensor devices. Herein, we generate highly extended silver nanoparticles (AgNPs) assemblies exceeding 20 microns in length in solution using controlled amounts of cysteamine. The self-assembly intensity of the ensembles is monitored by the growth of the anisotropic plasmonic band, which can be modulated by varying the ligand concentration, solvent intervention and pH. Scattering spectra for individual AgNPs ensembles on TEM grids were recorded under polarized light to reveal the effect of inter-particle aggregate size on the


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degree of inter-particle coupling. The spectra were correlated with the real particles configuration as revealed by TEM and STEM/HAADF enabling us to have individual spectral signatures. Discrete Dipole Approximation (DDA) simulations were done on individual particle ensembles to investigate the influence of aggregate size, light polarization, and nanoparticles polarizability on the observed spectra.

80. A bottom-up route to a chemically end-to-end assembly of nanocellulose fibers Han Yang, McGill University (Theo van de Ven) In this work, we take advantage of the rod-like structure of electrosterically stabilized nanocrystalline cellulose (ENCC), which has dicarboxylated cellulose (DCC) chains protruding from both ends, providing electrosterical stability for ENCC particles, to chemically end-to-end assemble these particles into nanocellulose fibers. ENCC with shorter DCC chains can be obtained by a mild hydrolysis of ENCC with HCl, and subsequently the hydrolyzed ENCC (HENCC) is suitable to be assembled into high aspect ratio nanofibers by chemically cross-linking HENCC from one end to another. Two sets of HENCC were prepared by carbodiimide-mediated formation of an alkyne and an azide derivative, respectively. Cross-linking these two sets of HENCC was performed by a click reaction. HENCC were also end-to-end crosslinked by a bioconjugation reaction, with a diamine. From atomic force microscopy (AFM) images, about ten HENCC nanoparticles were cross-linked and formed high aspect ratio nanofibers with a width of about 6 nm and a length of more than one micrometer.

81. Polynorbornene Ionomers as Polymer Electrolyte Membranes for Fuel Cells Lolwa Hajj Sleiman Haydar, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Ana Tavares) In this project, following our preliminary work [1-2], we are designing, synthesizing and testing new polynorbornene ionomers, which offer exceptional properties of thermal and chemical stability, for fuel cells. Firstly, new norbornene-based polymers are synthesized and characterized; secondly, these ionomers are used to prepare membranes for the measurement of transport properties; and thirdly, the most promising will be evaluated in a fuel cell.

1. J. C. Daigle, V. Dube-Savoie, A. C. Tavares, and J. P. Claverie, "Copolymers of ethylene and sulfonated norbornene for proton exchange membranes," J. Polym. Sci. Part A Polym. Chem., vol. 51, no. 12, pp. 2669-2676, 2013.

2. F. Pierre, B. Commarieu, A. C. Tavares, and J. Claverie, "High Tg sulfonated insertion polynorbornene ionomers prepared by catalytic insertion polymerization," Polymer (Guildf)., vol. 86, pp. 91-97, 2016.

82. Fast-drying graphene inks using tailored polymeric dispersants Ahmad Al Shboul, Université du Québec à Montréal (Jérôme Claverie) A highly conductive and fast dry pristine graphene inks were formulated by direct exfoliation of graphite using cholesterol polymer (poly(CEM11-b-EHA)7) in nonpolar solvent, isooctane. The cholesterol based stabilizer forms non-covalent supramolecular interactions with the conjugated systems.[1] Graphene inks were prepared by different cholesterol polymer content as a function of manipulating the surface coverage of graphene flakes with the polymer toward enhancing the electrochemical and structural properties of graphene inks. The sheet resistance (Rs) of graphene films prepared on glass plates increased with an increase of the surface coverage of graphene flakes. Rs levels reached approximately 690 Ω and specific capacitance 7.9 µF.cm-2 for a film thickness of 6 µm for 23% surface coverage of graphene flakes with the polymer. Modifying glass plates with HMDZ or coating with the cholesterol polymer exhibited further decrease of the sheet resistance for the same material cited above to 210 and 82 Ω, respectively. The limitations in the electrochemical properties with elevating the surface coverage of the graphene flakes indicates decreasing the π - π junctions in the graphene network, which hinders electrical charge transfer throughout the graphene film. However, enhancing the substrate hydrophobicity and morphology proportionally effect the charge transfer through enhancing flakes junctions that decrease sheet resistance.


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The presented graphene based ink formulation is expected to have a high potential competent with other conductive ink formulations of conductive films.

1. Nguendia JZ, Zhong W, Fleury A, De Grandpré G, Soldera A, Sabat RG, Claverie JP. Chem Asian J. 5 (2014) 1356-64.

83. Reprogramming and manipulating DNA assembly using simple molecular recognition principles

Nicole Avakyan, McGill University (Hanadi Sleiman) Supramolecular chemistry is the 'chemistry of molecular information'. Information stored in the structural features of molecules, is recognized and processed at the supramolecular level and drives the ever more complex organization of matter, from the formation of simple host-guest complexes, to the assembly of viral capsids and the emergence of life itself. Our goal is to use basic principles governing intermolecular interactions in order to manipulate the assembly of DNA, a molecule that exemplifies the storage of information in its structure. On one hand, we have expanded the DNA base-pairing alphabet, without making any synthetic modifications to DNA itself. We report that a small molecule, cyanuric acid, with three thymine-like faces reprograms the assembly of unmodified poly(adenine) into micron-long fibers with a unique internal structure. Our studies are consistent with the association of adenine and cyanuric acid units into a hexameric rosette, bringing together poly(adenine) triplexes with subsequent cooperative polymerization. Fundamentally, we show that a small hydrogen-bonding molecule can induce nucleic acid assembly in water, forming a new structure from inexpensive, readily available materials. On the other hand, we have manipulated the long-range assembly of DNA tile networks by interfacing them with supported lipid bilayers, a fluid, soft substrate. The DNA tiles are modified with hydrophobic anchors that can be used to selectively pattern different lipid domains with highly organized DNA lattices. In turn, these lattices represent a tool for organizing materials such as nanoparticles or proteins at a biological interface, with potential applications in cellular recognition, drug delivery and light harvesting.

84. Design and Synthesis of siRNA-Encapsulating DNA Nanocages for Conditional Release based on Oligonucleotide Sequence Recognition

Katherine Bujold, McGill University (Hanadi Sleiman) Oligonucleotide therapeutics are very potent and specific inhibitors of gene expression that show promise for the treatment of diseases with known deregulated genetic expression such as cancer. However, their selective delivery to tumor cells is hampered by the low stability of RNA in the extracellular environment and its poor uptake by the cell membrane. We propose to harness the power of DNA nanotechnology to address these shortcomings by assembling oligonucleotide therapeutics inside a DNA cage specifically designed to protect and deliver them to a cell line of interest. We demonstrate the assembly of a sequence-responsive DNA cage that can selectively release a functional small interfering RNA (siRNA) on demand. Our design comprises six strands which form a prism around a chosen siRNA. In order to bind the prism, the sense strand of the siRNA was elongated on both ends without altering its activity. Its release is mediated using a single-stranded portion on the prism which is complementary to a target of interest. This allows for a dual-action therapy as this single-stranded sequence can be made to be an antisense oligonucleotide or an antagomir. The encapsulated siRNA is released conditionally by strand displacement upon recognition of the target. The cage ensures protection of its cargo from nucleases and can be decorated with targeting molecules which include aptamers and a Teflon-like small molecule that allow its internalization in cancer cell models and primary skin cells.


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85. A facile route towards synthesizing ultra-small near infrared quantum dots Long Tan, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Dongling Ma) Solution processable PbS quantum dots (QDs) have attracted increasing attention in the fields of optoelectronics, biological imaging, etc. due to their size tunable optical properties in the near infrared range arising from the quantum confinement effect. To date, a so-called hot injection approach is well-known to lead to the highest quality, monodisperse PbS QDs with good size-tunability and thereby tunable, well defined optical characteristics. Regarding precursors used in the hot-injection method, S is less toxic and easily controllable than another well-known chemical, bis(trimethylsilyl) sulfide, as sulfur source. Nonetheless, the synthesis involving S (denoted as the S-route) usually leads to larger QDs. In our project, we have successfully synthesized ultra-small PbS QDs as small as 2.2 nm in diameter by modifying the S-route. Such synthesized PbS QDs with different diameters show good dispersity, high photoluminescence, narrow size distribution and stable colloid property, holding high potential for various applications. Moreover, it has been verified that the S-route can be easily scaled up.

86. Synthèse de nanoparticules d'or pour l'optimisation de la médication contre le glaucome Mathieu Ouellette, Université Laval (Élodie Boisselier) CONTEXTE ET OBJECTIFS : L'augmentation de la pression intraoculaire (PIO) constitue un important facteur de risque dans l'apparition d'un glaucome, car elle est susceptible d'endommager de manière irréversible le nerf optique et de mener à une perte de la vision. Cependant, les médicaments actuellement utilisés pour réduire la PIO pénètrent difficilement dans l'œil jusqu'à leur site d'action. En effet, plusieurs barrières physiologiques protectrices empêchent les agents étrangers d'y accéder. Il s'avère donc nécessaire de développer un système de relargage permettant d'améliorer la médication contre le glaucome. L'hypothèse de ce projet est basée sur l'utilisation des nanoparticules d'or (NP) en tant que vecteurs de médicaments ainsi que sur leur propriété de liaison aux protéines du film pré-cornéen afin d'augmenter considérablement la biodisponibilité et l'efficacité des médicaments contre le glaucome. MATÉRIEL ET MÉTHODES : La synthèse chimique et la purification de NP stabilisées par différents groupements polyéthylène glycol (PEG) ont été mises au point et optimisées. L'étude de l'encapsulation du travoprost, molécule très hydrophobe utilisée actuellement pour traiter le glaucome, a été réalisée par spectroscopie UV-visible et diffusion dynamique de la lumière. Les propriétés mucoadhésives des NP ont été étudiées par spectroscopie UV-visible ainsi que par une méthode de quantification colorimétrique. RÉSULTATS : Les mucines sont en mesure de se lier efficacement aux NP jusqu'à leur cœur métallique. De plus, les PEG constituent un environnement favorable permettant d'encapsuler plusieurs molécules de travoprost. Les NP stabilisées par du PEG de masse molaire 2000, ou encore par du PEG 1000 possédant une fonction thiol en surface, sont notamment prometteuses. CONCLUSION : Ces travaux répondent à une problématique actuelle qui est la faible biodisponibilité des médicaments contre le glaucome administrés par la voie topique. à terme, si les propriétés mucoadhésives des NP se confirment, cette stratégie pourrait être utilisée pour des médicaments visant d'autres muqueuses, telles que celles respiratoires, sexuelles, digestives et buccales.

87. LPCM Soldera François Godey, Université de Sherbrooke (Armand Soldera) The research being done in our laboratory aims to better understand the link between molecular and macroscopic properties, combining simulation, experiment and theory. We focus on phase transitions in soft matter such as polymers, crystals or organic glasses. Through an intimate dialogue within this triumvirate at each spatiotemporal level, it becomes possible to account for microscopic phenomena, giving rise to a macroscopic property, thus leading to the onset of phase transitions. Ultimately, our aim is to design new materials with improved structural, dynamical and functional properties.


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88. Green synthesis of graphene oxide hydrogels with superior mechanical properties and water contaminant adsorption capacity

Nariman Yousefi, McGill University (Nathalie Tufenkji) As the most recent member of the carbon family of nanomaterials, graphene oxide (GO), with its exceptionally high specific surface area, has been used for removal of dyes, heavy metal ions, oils and organic solvents from contaminated waters. However, recovery of GO after the decontamination process is difficult due to its highly stable nature in aqueous environments. Thus, self-assembly of GO sheets into porous 3D macrostructures such as hydrogels has been explored as a technique to exploit their high surface area while facilitating easy recovery from treated water. Still, forming mechanically robust hydrogels with acceptable adsorption capacities has been a significant challenge. We report a facile, green and one-pot method for preparation of ultra-strong GO hydrogels at low pressure by using vitamin C (VC) as a natural cross-linker. Using microscopy and spectroscopy techniques, we show that GO:VC ratio is a critical factor that dictates the micro- and macrostructure of the hydrogels, which affect their mechanical and adsorption properties. We demonstrate that hydrogels with storage moduli as high as 330 kPa can be used to effectively remove model dyes such as methylene blue (adsorption capacity of 350 mg/g) and emerging contaminants such as diclofenac (adsorption capacity of 40 mg/g) and sulfamethoxazole (adsorption capacity of 25 mg/g) from aqueous solutions. The use of ultra-large GO sheets, highly porous structure of the hydrogels and finally, the abundance of oxygen-containing functional groups are the major reasons behind their excellent adsorption capacity.

89. Photocatalytic Lithography for Polymer Brushes Engineering Guido Soliveri, Polytechnique Montréal (Antonella Badia) Polymer brushes, stretched arrays of polymer chains chemically attached to a surface, are powerful tools for surface engineering, in fields ranging from biochemistry to electronics [1]. In the 'grafting-from' approach, a surface-immobilized initiator allows the growth of polymer brushes directly from the surface. If the initiator layer is patterned, patterned brushes will be obtained. In this work, we exploit the well-known photocatalytic properties of titanium dioxide in the initiator patterning. Titanium dioxide is currently a protagonist in advanced lithographic techniques due to its eco-friendliness and low cost [2]. Compared to classic photolithography, photocatalytic lithography allows the patterning of polymer brushes (with micrometer resolution) with unprecedented ease: it does not require resists and intense UV sources. Here, initiators of polymerization were grafted on different substrates, patterned using direct and remote photocatalytic lithography, and amplified into polymer brushes [3]. In addition to electron and scanning microscopy analysis, electrochemistry was used to provide a better understanding of the polymer brush behavior with and without patterning [4]. We demonstrate photocatalytic lithography as an easy route to preparing functional surfaces, with potential applications ranging from sensor technology (e.g. molecular recognition) to microfluidics.

1. R. Barbey, L. Lavanant, D. Paripovic, N. Schüwer, C. Sugnaux, S. Tugulu, H.-A. Klok, Chem. Rev. 2009, 109, 5437-5527. 2. A. Fujishima, X. Zhang, D. A. Tryk, Surf. Sci.Rep., 2008, 63, 515-582. 3. G. Panzarasa, G. Soliveri, K. Sparnacci, S. Ardizzone, Chem. Commun., 2015, 51, 7313-7315. 4. G. Panzarasa, G. Soliveri, V. Pifferi, J. Mater. Chem. C, 2016, 4, 340-347.

90. Controlled synthesis of Pd and Pt nanotubes via lipid tubule templating and their application in catalysis

Yinan Wang, Institut National de la Recherche Scientifique - Énergie, Matériaux, Télécommunications (Shuhui Sun) Palladium and platinum nanotubes were fabricated using lipid tubules as templates for the first time in a controlled manner. The lipid tubule formation was optimized by studying the growing dynamics, ethanol/water ratio. The lipid tubules showed pH stability from 1 to 14, which make them ideal templates for


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metal plating. The Pd and Pt nanotubes are open end and exhibit excellent electrocatalytic performance. The electrochemically active surface areas (ECSA) of Pd nanotubes can be controlled by tuning the tube wall thickness. The Pt nanotubes show excellent activity for hydrogen evolution reaction (HER). The method developed herein opens up a way for controlled fabrication of noble metal nanotubes, which have great potential for catalysis in fuel cells.

91. Materials for nanotechnology and energy- A path to a sustainable future Midhun Mohan, Université du Québec à Trois-Rivières (Adam Duong) L'équipe DuongLab est localisée à l'Université du Québec à Trois-Rivières à l'Institut de Recherche sur l'Hydrogène et au département de chimie, biochimie et physique. Nous sommes intéressés à la conception, à la synthèse et à la caractérisation de matériaux innovants pour le développement de l'énergie et de la nanotechnologie. Nos objectifs sont de fabriquer des matériaux pour la conversion et le stockage d'énergie pour explorer les domaines de l'électrochimie, du photovoltaïque et de l'optoélectronique. Nos stratégies de synthèses reposent sur la chimie organique, organométallique et inorganique pour préparer des nanostructures de carbones, des Covalent Organic Frameworks (COFs), des Metal Organic Frameworks (MOFs) et fonctionnaliser le graphène.

92. Développement De Nanoparticules D'or Pour Le Relargage De Médicaments Contre Le Glaucome

Mahmoud Omar, Université Laval (Élodie Boisselier) CONTEXTE ET OBJECTIFS: Le glaucome est la deuxième cause de cécité au monde. Cette maladie est souvent associée à une élévation de la pression intraoculaire (PIO) qui provoque la dégénérescence du nerf optique et de la rétine. L'administration topique de médicaments visant à réduire la PIO, sous forme de gouttes ophtalmiques sur la cornée, a une action thérapeutique limitée. Ce problème est attribué à l'élimination rapide des médicaments de la surface de la cornée et à leur faible pénétration dans lœil. Notre hypothèse est que les nanoparticules (NP) pourraient servir de vecteurs pour des médicaments tels que le travoprost (TV), et pourraient de cette façon améliorer les traitements du glaucome. Les objectifs de ce projet sont de synthétiser des NP et d'évaluer leurs effets avec le travoprost sur la PIO dans un modèle de glaucome chez la souris. MATÉRIEL ET MÉTHODES: Des NP ont été synthétisées selon une méthode modifiée de Brust en formant un noyau d'or entouré de polyéthylène glycol permettant ainsi la biocompatibilité et la stabilité des NP. La taille des NP a été estimée par diffusion dynamique de la lumière. Un protocole d'encapsulation a été mis au point et évalué par spectroscopie UV-visible (UV). Un modèle de glaucome a été induit en injectant des microbilles de polystyrène dans la chambre antérieure de souris C57BL/6J. Cette approche consiste à boucher le trabéculum, c'est-à-dire le système de drainage de l'humeur aqueuse, et ainsi augmenter la pression dans lœil. L'augmentation de la PIO a été mesurée avec un tonomètre de manière non-invasive et quotidienne jusqu'au retour à la normale. RÉSULTATS: Les NP ont été synthétisées et caractérisées par UV (bande plasmon à 526nm, n=5) et par diffusion dynamique de la lumière (diamètre hydrodynamique de 21.03 nm). L'encapsulation du TV a été mise en évidence par un déplacement des bandes observées en UV des NP et du TV. La stabilité des NP et la cinétique d'encapsulation ont également été étudiées pendant plusieurs jours par UV. Par ailleurs, la PIO des souris augmentait de 62% par rapport à leur niveau de départ 7 jours après l'injection des microbilles de polystyrène. L'élévation de la PIO était maintenue pendant 3 semaines. CONCLUSION: Les NP sont capables d'encapsuler le TV. Les effets combinés des NP et du TV seront prochainement testés sur la PIO dans le modèle de glaucome chez la souris.

93. The chain length of free fatty acids influences the phase behaviour of stratum corneum model membranes: A 2H-NMR and IR investigation

Adrian Paz Ramos, Université de Montréal (Michel Lafleur)


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Stratum corneum (SC), the outermost layer of mammal epidermis, is the main element of skin impermeability. It is formed by corneocytes embedded in a lipid matrix, which is mostly constituted by ceramides (Cer), free fatty acids (FFA) and cholesterol (Chol), organized in two coexisting crystalline lamellar phases. The diffusion of substances across the SC is proposed to proceed mainly via the intercellular lipid matrix and therefore, the understanding of the lipid matrix structure and of the molecular interactions dictating it is crucial for comprehending and controlling the penetration of substances through the skin. The aim of this work is to determine the impact of FFA chain length on the phase behaviour of SC model lipid membranes, using solid-state deuterium NMR and IR spectroscopy. We studied tertiary mixtures of N-lignoceroyl-D-erythro-sphingosine (Cer24), cholesterol, and palmitic (FFA16) or lignoceric (FFA24) acid in equimolar ratio. Our studies revealed that the phase behaviour of Cer24/FFA/Chol tertiary mixtures is deeply affected by the length of the FFA. We found the formation of phase-separated crystalline lipid domains when using palmitic acid while the use of lignoceric acid results in a more homogeneous mixture. FFA24 solid phase, observed in the mixture at low temperature, gains motional freedom at temperature lower than expected for such a long-chain FFA. In addition, mixtures with lignoceric acid form a gel phase, a very unusual feature for SC model mixtures. The reduction of FFA and ceramide chain length is reported in atopic eczema and atopic dermatitis patients. Coupling the reduction in lipid chain length with an altered phase behavior, such as less homogeneous lipid mixing, would constitute a major step forward in our understanding of the skin barrier.

94. Scanning Probe Microscopy (SPM) At The Laboratory of Characterization Of Materials (LCM) Patricia Moraille, Université de Montréal (Michel Lafleur) Since January 2001, the Laboratory for the Characterization of Materials (LCM) offers Quebec's research community access to a variety of state-of-the-art instruments. Research professionals provide training as well as technical support. We describe here, the various scanning probe microscopy (SPM) options that are available at the LCM. Beyond imaging topography, SPM can use a variety of forces to measure friction, visco-elasticity and compositional variations. SPM as a technique is not bound to specific environmental conditions, It can be performed in vacuum, air or water and at a variety of temperatures. The expertise and savoir-faire of this Lab makes it one of Quebec's specialized infrastructures for the imaging of nanostructured materials and thin films on the nanometer to micron length scales. Our SPM installation is used by more than 150 scientists yearly. Our facilities are opened to all researchers from both university and industry at affordable rates.

95. PbS/SWCNT, a new composite material for application in organic photovoltaic cell Hayet Cherfouh, Université du Québec à Montréal (Benoît Marsan) In this work, we have prepared and characterized a new composite material based on PbS nanoparticles combined with Single-Walled Carbon Nanotubes (SWCNT) for application as active material in an organic photovoltaic cell containing the conjugated polymer P3HT (poly(3-hexylthiophene-2,5-diyl)). PbS has been chosen because of its interesting optical and electronic properties, including direct absorption in the IR-region, combined with those of SWCNT, among them high electron mobility. PbS/SWCNT was prepared using a novel chemical method, with and without oleylamine (OLA) as organic ligand to prevent aggregation of PbS nanoparticles. X-ray diffraction analysis shows that PbS is growing in a face-centered cubic structure. Transmission electron microscopy allowed us to visualize semi-spherical particles with a diameter in the range of 2 to 10 nm, adsorbed on the surface of SWCNT. Chemical analysis demonstrates the presence of lead and sulphur (PbS), and carbon and oxygen (OLA and SWCNT) elements. Electrochemical impedance spectroscopy measurements show that the addition of carbon nanotubes (SWCNT) to a PbS film reduces significantly the charge transfer resistance. Capacitance measurements as a function of applied potential reveal an n-type behavior for PbS and a p-type behavior for P3HT.


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96. Effect of polystyrene and fluoropolymer culture surfaces on monocyte cell fate Natalie Fekete, McGill University (Corinne Hoesli) Cell therapy often requires the in vitro expansion or differentiation of donor-derived cells to generate the cell product of interest. For clinical-scale production, tissue culture-treated polystyrene-based culture vessels and bag bioreactor systems fabricated from fluoropolymers are available. Commercially available cell culture surfaces differ in various properties, including their chemical composition, surface topography and wettability. Thus, depending on the choice of culture surface and culture media, the cell-surface and protein-surface interactions at the biointerface may therefore be profoundly altered. The aim of this study was thus to investigate protein adsorption and cell response to fluoropolymer and polystyrene culture surfaces in the context of monocyte-based cell therapies. By using quartz-crystal microbalance with dissipation monitoring (QCM-D), we found rapid and irreversible protein deposition onto fluoropolymer surfaces. Incubation of fluoropolymer and polystyrene surfaces with cell culture medium resulted in increased wettability, surface free energy and altered the surface's chemical and mechanical properties. As adsorbed proteins may either facilitate or prevent cell adhesion to surfaces, we then investigated human monocyte fate in vitro. Peripheral blood-derived monocytes were cultured in polystyrene and fluoropolymer-based vessels and exposed to cytokine cocktails to induce their differentiation and maturation. Flow cytometry was employed to assess the expression of surface receptors characteristic for monocytes and their differentiated progeny, dendritic cells. The cultured cells showed comparable levels of viability, adhesion and aggregation during the first 2-3 days of culture. During the differentiation step, a complete loss of CD14 surface expression was observed, with concomitant upregulation of the antigen-presenting cell-specific surface markers. These results suggest that monocytes can be differentiated into dendritic cells on both fluoropolymer and polystyrene culture surfaces. In sum, differences in cell adhesion potential and rates may be related to differences in protein adsorption levels found at the interface of culture surfaces. Understanding cell-surface interactions at a molecular and mechanical level will allow the development of materials tailored for a variety of cell therapy applications.

97. Controlling the Surface Chemistry of Superparamagnetic Iron Oxide Nanoparticles Shoronia Cross, McGill University (Amy Blum) Iron oxide nanoparticles (IONPs) have been recognized as ideal materials for use in applications such as magnetic resonance imaging (MRI) contrast agents, drug targeting, and separation technologies, due to their magnetic properties, low toxicity, and low cost. The ability to selectively modify the surface coatings of the particles is essential for tuning the physical and chemical properties of IONPs for specific applications. We report a method for creating aqueous stable IONPs by performing solvent phase ligand exchange on oleic-acid capped IONPs, using a mixture of DOPAC (3,4-dihydroxyphenylacetic acid), and Tiron (4,5-dihydroxy-1,3-benzenedisulfonic acid). We further demonstrate that the surface chemistries of these DOPAC and Tiron-capped IONPs (IONP-DOPAC/Tiron) can be tuned through the use of a combination of EDC coupling and click chemistry. We first coupled propargylamine through the DOPAC ligands using EDC, which then provided an exposed alkyne through which Cy5-azide dye could be bound using the copper-catalyzed azide-alkyne cycloaddition reaction. This proof of concept illustrates the versatility of IONP-DOPAC/Tiron as a starting material for selective functionalization of superparamagnetic IONPs.

98. Preparation and characterization of Soft-Bonded Azo Polymer Complexes for Photo-Reversible BioCompatible Materials

Frédéric-Guillaume Rollet, McGill University (Christopher Barrett) Azobenzene dyes represent an interesting class of molecules for their potential use as photo-switches due to their fast, powerful and reversible trans-cis isomerization. Due to these properties, they have been


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incorporated in thin films to create photo-responsive bio-compatible surfaces. Previous efforts in creating bio-compatible surfaces covalently bind the azo moiety to the polymer backbone. However, covalent binding of the azo dye to the polymer backbone often requires long synthesis steps and intricate purification procedures, with uncertain biocompatibility. Herein, we investigate new systems using non-covalent interactions, such as ionic or hydrogen bonding. Films of polyvinylpyrrolidone (pVP) and disperse red 1 (DR1) or methyl red (MR), have been prepared as successful azopolymer complexes. The extent of dye loading and nature of the binding in these films is monitored by DSC, IR and UV-Vis spectroscopy. The interaction between dye and polymer show up to a 15 cm-1 shift in the IR uC=O band of pVP for both DR1 and MR. Broadening of the band by about the same wavenumber indicates a mixture of bound and unbound species. Further evidence of binding is shown in DSC profiles by the absence of dye melting at lower dye ratios. A blue shift is observed in the UV-Vis spectra of DR1 and MR complexes upon exposure to pure water vapour or high humidity air. DR1 complexes change readily upon exposure to humid air and exhibit reversibility upon heating, whereas the effect is much slower and irreversible with MR complexes.

99. Synthèse et caractérisation du semi-conducteur CuGaS2 pour la photoelectrolyse de l'eau Kassoum Sangare, Université du Québec à Montréal (Benoit Marsan) La production photocatalytique d'hydrogène à partir d'une solution aqueuse et d'un matériau semi-conducteur constitue une méthode de conversion de l'énergie solaire en énergie chimique très intéressante. Plusieurs travaux réalisés dans l'ultra-violet ont conduit à des rendements prometteurs. Le défi majeur réside dans la mise au point d'un photocatalyseur capable de fonctionner de façon efficace dans le visible, pour une meilleure utilisation de l'énergie solaire. Dans ce travail, nous avons réalisé la synthèse colloïdale du semi-conducteur CuGaS2 en faisant réagir sous argon les composés GaCl3 et Li2S, dissous séparément dans le 1-methylimidazole (NMI), pour former le précurseur LiGaS2 auquel a été ajoutée une solution de CuCl/NMI, menant à une suspension de CuGaS2 ensuite traitée à 80 °C pendant 20 h. Un ratio Cu:Ga:S de 1:1,05:2,1 a été employé et les particules brune filtrées ont été recuites sous vide à 600 °C et 500 °C durant 2 h. L'analyse chimique confirme une composition riche en gallium avec un ratio atomique Ga/Cu de l'ordre de 1,08, suggérant un semi-conducteur de type n. La diffraction des rayons X confirme la phase chalcopyrite du matériau et révèle une taille des cristallites de l'ordre de 20 nm et 12 nm respectivement. La bande interdite de CuGaS2 est une transition directe, estimée à 2,4 eV par spectroscopie UV-Visible. Des caractérisations électriques permettront de confirmer le type n et de déterminer le niveau de Fermi ainsi que la densité des porteurs de charge majoritaires du semi-conducteur.

100. Effect of estradiol conjugated chitosan phosphorylcholine polymer prodrug on the cardiovascular system

Baowen Qi, Université de Montréal (Françoise Winnik) Estradiol (E2) is an essential female hormone in the regulation and determination of various physiological conditions in vivo, such as cell proliferation and differentiation. When supplementing exogenous E2 as a clinical strategy for hormone therapy, it generates genomic and non-genomic effect simultaneously via binding to the estrogen receptors in the cell nucleus or membrane site. Compared to the genomic effect, it is quite difficult to monitor the E2-induced non-genomic biological behavior because: 1) this effect occurs in extremely transient time scale. 2) The bioavailability and accessibility of E2 to target cells is very low due to the hydrophobic nature of E2. As a result, it is indispensable to develop E2 delivery systems to specifically understand estrogenic non-genomic nature. One of strategies is to graft E2 to the hydrophilic macromolecules, e.g. bovine serum albumin (BSA) or poly(amido)amine dendrimer, to maintain E2 interacting with membrane estrogen receptors instead of penetrating into the cell nucleus. However, the instability of those E2-macromolecules systems, either containing free E2 leaching or discrepancies of cellular


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localizations, led to controversies. Herein, the objective of present thesis is to develop novel E2-functionlized platforms by the principle of bottom-up and top-down approaches for understanding the mechanism of estrogenic non-genomic effect, and further, to explore their potential applications in the biomedicine. As a bottom-up approach, an activated E2 ligand, 17α-ethinylestradiol-benzoic acid was covalently conjugated onto a phosphorylcholine substituted chitosan polymer (CH-PC-E2) as a prodrug strategy for the fabrication of self-assembled films. Through a series of combined physicochemical and cellular investigations, the relationship between various chemical compositions of chitosan-phosphorylcholine (CH-PC) films and cellular responses was also evaluated. Based on atomic force microscopy (AFM) examination, zeta-potential measurements, surface plasmon resonance (SPR), and quartz crystal microbalance with dissipation (QCM-D) measurements, surface topography, charge, and rheology of CH-PC films with 15, 25, and 40 mol% PC contents were characterized. Moreover, QCM-D measurements indicated that the amount of fibrinogen adsorbed on CH-PC films decreased significantly with increasing PC content. Finally, it was also shown that human umbilical vein endothelial cells (HUVECs) form spheroids on CH-PC25 and CH-PC40 films, but not on CH-PC15 films cultured over 4 days. Moreover, the CH-PC-E2 polymer conjugates were prepared and characterized by several techniques, such as 1H nuclear magnetic resonance (1H NMR), Fourier transformed infrared-attenuated total refraction (FTIR-ATR) and UV/Vis spectra measurements. Moreover, the hydrogel nature of CH-PC-E2 film as well as its interactions to estrogen receptors was extensively investigated by QCM-D study. In the cellular study, CH-PC-E2 hydrogel films can significantly stimulate the production of nitric oxide (NO), a protective molecule in the cardiovascular system, in the endothelial cells by a diaminofluorescein-FM diacetate (DAF-FM) imaging study. The studies above demonstrated the different roles and potential applications of CH-PC-E2 and CH-PC surfaces in the cardiovascular regenerative medicine. As a top-down approach, micropatterned substrates were used for E2 functionalization, which were prepared by photolithography via aligning ~ 2 µm in diameter gold arrays onto a glass substrate. After that, a cell adhesive peptide, cyclic RGD was introduced to the glass surface in order to induce the attachment of cells. Meanwhile, estradiol was covalently immobilized on the gold surface and the process was monitored and validated by combining SPR and QCM-D studies. In the micropatterned substrate-coupled cell ELISA study, a phosphorylation level of extracellular signal-regulated kinase (ERK), which is an important non-genomic marker, was significantly elevated by this E2-functionalized micropatterned surface after 1 hour incubation. Furthermore, E2-functionalized micropatterned substrate didn't proliferate cancer cells indicating the absence of genomic effect stimulation. Based on these results, our E2-functionalized micropatterned substrates can function as an in vitro model for the elucidation of estrogenic non-genomic behaviors.

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Abstract booklet (777 kB)