Selenide and telluride glasses for mid-infrared bio-sensing

Selenide and telluride glasses for mid-infrared bio-sensing Shuo Cuia,b, Radwan Chahala, Yaroslav Shpotyuka, Catherine Boussarda, Jacques Lucasa, Frederic

Charpentierc, Hugues Tarielc, Olivier Loréald, Virginie Nazabala, Olivier Siree, Valérie Monbetf,

Zhiyong Yangg,‡, Pierre Lucasg, Bruno Bureaua1

aEquipe Verres et Céramiques UMR-CNRS 6226 Institut des Science Chimique de Rennes,

Université de Rennes 1, France. bDepartment of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.

cDIAFIR Company, Le Gallium, 80 avenue des buttes de coesmes, 35700 Rennes, France. d INSERM UMR991, Université de Rennes 1, 35033 Rennes, France.

eLIMAT-B, Université Européenne de Bretagne, Université de Bretagne-Sud, 56017 Vannes,

France fIRMAR, UMR 6625, Université Européenne de Bretagne, 35042 Rennes, France.

gDepartment of Materials Science and Engineering, University of Arizona, 4715 E. Fort Lowell

Road, Tucson, AZ 85712, USA ‡ now at Australian National University, Canberra, Australia

ABSTRACT

Fiber Evanescent Wave Spectroscopy (FEWS) is an efficient way to collect optical spectra in situ, in real time and even, hopefully, in vivo. Thanks to selenide glass fibers, it is possible to get such spectra over the whole mid-infrared range from 2 to 12 µm. This working window gives access to the fundamental vibration band of most of biological molecules. Moreover selenide glasses are stable and easy to handle, and it is possible to shape the fiber and create a tapered sensing head to drastically increase the sensitivity. Within the past decades, numerous multi-disciplinary studies have been conducted in collaboration with the City Hospital of Rennes. Clinical trials have provided very promising results in biology and medicine which have led to the creation in 2011 of the DIAFIR Company dedicated to the commercialization of fiber-based infrared biosensors. In addition, new glasses based on tellurium only have been recently developed, initially in the framework of the Darwin mission led by the European Space Agency (ESA). These glasses transmit light further into the far-infrared and could also be very useful for medical applications in the near future. Indeed, they permit to reach the vibrational bands of biomolecules laying from 12 to 16 µm where selenide glasses do not transmit light anymore. However, while Se is a very good glass former, telluride glasses tend to crystallize easily due to the metallic nature of Te bonds. Hence, further work is under way to stabilize the glass composition for fibers drawing and to lower the optical losses for improving their sensitivity as bio-sensors. Keywords : mid-infrared spectroscopy, optical fiber, chalcogenide glass, selenium, tellurium. 1 Correspondence : Email : [email protected], Telephone : 33 (0) 2 23 23 65 73, Fax : 33 (0) 2 23 23 56 11

Invited Paper

Optical Fibers and Sensors for Medical Diagnostics and Treatment Applications XIV, edited by Israel Gannot, Proc. of SPIE Vol. 8938, 893805 · © 2014 SPIE · CCC code: 1605-7422/14/$18 · doi: 10.1117/12.2036734

Proc. of SPIE Vol. 8938 893805-1

Downloaded From: http://proceedings.spiedigitallibrary.org/ on 05/07/2014 Terms of Use: http://spiedl.org/terms

1. INTRODUCTION

Chalcogenide glasses are well known materials developed mainly for their optical properties in the infrared region1,2. Indeed they transmit light further in the mid-infrared than any other vitreous material. Moreover their glassy state makes them easy to shape into optical devices such as lenses, thin films, coatings, planar waveguides or optical fibers (Figure 1). One of the most promising applications for these fibers consists in implementing remote mid-infrared spectroscopy, called FEWS for Fiber Evanescent Wave Spectroscopy3. The optical transmission of such fibers ranges from 2 to 25 µm, depending on the glass composition. It encompasses the vibration domain of most chemical and biological molecules. Chemical detection using chalcogenide glass fibers was firstly reported in the late 1980s and 90s with the characterization of butanone4, on acetone, ethanol, and sulfuric acid 5,6, and then benzene, toluene, and trichloroethylene were studied7,8. Note that, AgCl/AgBr polycristalline fibers had also been developed for chemical sensing 9-12. They transmit light up to 20 µm in the infrared range and, from a mechanical point of view, they are more flexible and easy to handle than glass fibers. On the other hand, polycrystalline fibers made from AgCl/AgBr salts are very sensitive to air and water contamination which deteriorates their optical transparency. Moreover, their sensitivity to evanescent wave detection is affected by their large diameter, around 1 mm compared to less than 100 µm for tapered glass fibers in the sensing head. Recently, mid-IR sensors based on selenide glasses have been successfully produced and used for environmental and biomedical applications, in the framework of multidisciplinary research programs. These studies include detection of pollutants in waste water 13,14, monitoring of chemical processes 15,16, detection of bacterial contamination in food 17, monitoring of bacterial biofilm spreading 18,19, metabolic imaging of tumorous tissues 20,21, lung cell contamination 22-24 and biological fluids such as serum, or plasma 25. The most promising applications surely deal with biology and medicine 18-27 and they have led to the founding of a start-up company, called DIAFIR 28. DIAFIR aims at developing a global method of mid-IR sensing including glass optical fibers and statistical analysis integrated into the chain of measurements.

2. SELENIDE GLASS FOR FIBER EVANESCENT WAVE SPECTROSCOPY

Figure 1: Some examples of optical elements made of chalcogenide (selenide) glasses: optical fiber, large bulk of glass, molded optical lenses, planar waveguide, micro-structurated fiber and microsphere. The outstanding rheological properties permit to produce large optics or to shape the glass into the desired configuration. Most of these devices are under development for sensing application working in the mid-infrared range.



2.1 General principle

When a light wave propagates in a material of higher refractive index than the surrounding air, the light is trapped within the material through total internal reflection. Thus, the light wave can propagate through a fiber without energy loss other than that associated with intrinsic absorptions due to impurities. The interference between the incident and the reflected waves gives rise to standing waves inside the waveguide, perpendicular to the interface, and to the generation of an evanescent field inside the sample. The evanescent wave decreases exponentially as it propagates into the sample, away from the fiber surface. Fiber Evanescent Wave Spectroscopy is a practical method to record infrared spectra that enable in-situ and real-time measurements. The flexibility of such a system and the ability to transmit optical signals over a long distance via the fiber, make such sensors very attractive for chemists, biologists and physicians. The advantage of this technique is to perform remote, real-time and in situ analysis. The FEWS method is quite simple to implement since the measurement necessitates only a standard spectrometer equipped with special attachment for focusing the light and an MCT detector (Figure 2). Figure 2: general set up to implement Fiber Evanescent Wave Spectroscopy experiments. A unique optical fiber permit to transport the signal from the source to the sample and back to the detector (MCT cooled by liquid nitrogen). 2.2 Selenide glass optical fibers

The specific issues in glass science is to know how to play with glass composition to get the expected properties, and the mastering of the synthesis methods including the purification steps to obtain some highly purified glass essential for light transmission into the fiber. For applications in mid-infrared spectroscopy, the main requirements concerning the choice of the composition are a large transmission window in the infrared, thermo-mechanical properties allowing the elaboration of optical fibers, a glass transition temperature high enough to permit manipulations at room temperature and a good chemical durability. In the infrared, the optical transmission is limited by the chemical bonds vibrations of the glassy network. Thus, the heavier the chemical elements are, the lower the vibration frequencies of chemical bonds are. Consequently, glasses containing heavy elements possess a broad transparency window in the infrared. Tellurium-based glasses are the glasses that present the lowest absorption in the infrared, following sulphur and selenium-based glasses. This results in a red-shift of optical transmission in the S to Se to Te series. However, glasses containing high amounts of tellurium, more than 70 mol %, show a high tendency to crystallize and are difficult to shape into optical fibers. So, it is essential to add large amounts of selenium in Te-based glass compositions to achieve stability of the glassy state. At this time, the best compromise is the Te2As3Se5 glass composition, referred to as TAS glass. The structure of this glass is constituted of Se and Te chains rigidified by the introduction of trivalent arsenic atoms that reticulate the chains29,30. Thus, this glass is very stable thanks to its strong covalent bonds, and its thermo-mechanical properties allow an easy shaping into fiber (Tg=137°C). The transparency of glass disks extends from 2 to 16 µm. Important steps of chemical

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purification are necessary to improve the transparency of this glass by reducing the presence of impurities such as oxygen, hydrogen, carbon, silicon. This broad and optimized transparency is strictly required to achieve the highest sensitivity with the sensor. The second point concerns the fabrication of the optical fiber in specific drawing facilities suitable for low Tg glasses such as the TAS composition. Indeed, the sensor consists in a unique single-index optical fiber which, first, transports the infrared signal from the black body source to the detector and, second, detects a sample by simple immersion or contact. In order to maintain high transparency, it is essential that the glasses be synthesized in very high purity. In particular, all traces of low-mass impurities must be carefully removed as they would generate absorption within the optical window which would alter the optical quality. This is a particularly significant problem in glass fibers where the optical path is very long and where even traces amount of impurities would generate unacceptable losses and render the fiber opaque in the spectral region of interest. The full synthesis must also be performed under high vacuum or controlled atmosphere in order to avoid contact with oxygen. After these purification steps, fiber losses as low as 0.5 dB.m-1 can be reached. This value, far from the attenuation of silica fibers (10-2 dB/Km at 1.55 µm) is low enough to permit short distance applications but the definitive advantage compared to silica fibers is a transparency range extending far beyond 2 µm up tol 12 µm. 2.3 Decisive points to get fruitful information In the recent past, it has also been shown that the number of reflections at the glass/air interface depends on the fiber diameter according to the formula: Where z is the length of contact between the fiber and the sample, θ is the incident angle, and d the fiber diameter in the sensing zone. According to this basic formula, the sensitivity should be higher for smaller fiber diameter. This has been verified experimentally on different context, see figure 3. The classical design used for FEWS is a unique fiber with a diameter equal to 400 µm with a tapered diameter of 100 µm for the sensing zone. Thanks to the glassy state of the fiber, this can be easily achieved on-line during the fibering process by accelerating the drum speed, or afterward in a second step by chemical etching. This achievement is a critical point to get an interesting sensitivity in particular in biology and medicine. The second critical point deals with the chemical nature of the TAS glass which is strongly covalent. Thus, the glass surface of the fiber displays a hydrophobic character which promotes stronger interactions with organic molecules than with water. This provides a notable benefit for IR sensing due to the strong water signal that often overlap with the signature of target molecules. This basic property of selenide glass is also crucial in the framework of medical or biological studies. Figure 3: (a) Correlation between fiber diameter and detection sensitivity based on geometric optics. Smaller fiber diameter lead to increasing number of absorption events along a given section of fiber. (b) Microscope image of tapered fiber sensing zone. The original fiber diameter is around 400 microns permitting to easily focus the light from the black body source into the fiber. The taper diameter is classically equal to 100 µm. (c) Increase in sensitivity of the detection of acetone after reduction of the fiber diameter from 400μm to 100μm.

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At last, mid-infrared fingerprints of bio-molecules contain much information on cells metabolism which can help distinguish between healthy and altered tissues or biological liquid. The collected FEWS spectra are even too rich and complex and, in most of the real life studies, they are very similar and it is impossible to classify them. In that respect FEWS combined with adequate statistical analysis can yield sufficient spectral fingerprints to perform a rapid classification of patients with metabolic dysfunctions. This provides relevant information for the diagnosis of specific diseases. To achieve this goal, one has to carry out some unsupervised statistical analysis method such as Principle Component Analysis (PCA) or Partial Least Square (PLS) regression. PLS is clearly the most efficient tool for final users like physician. On the other hand, as an initial step, PCA provide nicer and more pedagogic maps in which each spectrum is represented as point in two or three dimensions spaces. The spectra belonging to the same family (healthy or not) are expected to be gathered in the same part of the space permitting to distinguish them. 2.4 Large scale study on human serum Recently, PCA and a PLS logistic method have been applied in a clinical trial to identify patient affected with four metabolic disfunctions including hemochromatosis, iron depletion, cirrhosis, and dysmetabolic hepatosiderosis 25. FEWS was carried out using the above TAS glass tapered fibers in order to analyze serum from a large group of patients (around 400 serum spectra collected). It was shown that PLS logistic provided an effective mean of discriminating patients from each group. This statistical analysis method indeed appears to be very promising for medical diagnostics. As an illustration of this promising collaboration with the Public Hospital in the city of Rennes, one provides the following PCA map corresponding to hemochromatosis patients (Figure 4). Hemochromatosis is a hereditary disease characterized by an excess of iron in the intestinal absorption. Among other fruitful collaborative works, the study led on human sera is at the origin of the founding of a start-up company in Rennes, called DIAFIR28. Figure 4: serum spectra (on the left) collected from healthy and hemochromatotic patients. The construction of the 3D PCA map (on the right) permitted to fairly differentiate the both families. The PCA was implemented on the range 1438-1468 cm-1.

3. What could bring Telluride glass 3.1 Telluride glass for FEWS ? Recently, tremendous interest has been focused on the exploration of the Universe. For that purpose, the Darwin mission led by the European Space Agency (ESA) requires fibers capable of observing the CO2 absorption band located around 15 µm. The most efficient strategy to expend the optical window of chalcogen glasses is to use heavy atoms such as tellurium in order to lower the phonon energy and push the multiphonon cut-off to longer wavelength. Thus, tellurium-based glasses, called telluride glass, can transmit light further in the infrared region up to 28 µm due to

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their atoms’ heaviness 31. That principle has successfully been applied to produce telluride glasses with good thermal stability and transmission up to 22 μm. Unfortunately, Se and Te are totally opposite in terms of their ability to form glassy materials. Whereas Se is a very good glass former, telluride glass tends to crystallize easily due to the metallic behavior of Te. So, the elaboration of pure Te-based glass is a clear issue and the manufacture of optical fiber is very challenging. Nevertheless, among telluride glasses, the Te-Ge-As, Te-Ge-Ga, Te-Ge-Se, Te-Ge-I systems have shown exceptional glass forming stability and we have recently demonstrated the production of optical fibers 31-35. Figure 5: comparison between the attenuation curve of the TAS glass (on the left) and the Ge21Te76Se3 glass fibers. For the TAS glass, the absorption peaks at 4.5 and 6.3 µm are attributed to the vibration modes of the Se-H bonds and the H2O molecules, respectively. On the right, the noise around 15-16 µm could be due to CO2 strong absorption band arising at this wavelength. To illustrate what tellurium based glass could bring in the future to biomedical infrared spectroscopy, Figure 5 compares the attenuation curve of the highly purified TAS glass to the attenuation of a Ge21Te76Se3 glass fiber 34. These last fibers have been developed in the framework of the DARWIN mission and permit to detect CO2 near 15µm in transmission mode. More generally, they should enable to detect any vibration band resonating between 12 to 16 µm whereas the TAS glass fibers do not transmit infrared light anymore. Thus, telluride glasses, by exploring the 12 to 16 µm (1000-670 cm-1) spectral domain, will permit to study a domain not currently explored by using selenide glasses. Overall, these extended optical domains may give novel specific information about target analytes. This domain of the spectrum is dominated by polysaccharides and nucleic acids vibrational modes. In addition, aromatics C-H and primary amines may also be detected. On the other hand, as observed on figure 5, the main drawbacks associated with high Te content is the resulting decrease in band-gap energy which generates high densities of free charge carriers at room temperature. This is highly problematic in optical fiber technology because free-charge carriers are known to produce significant background losses which lead to high intrinsic background absorption that cannot be improved through purification. In the future, one needs to work on new glass composition combining low phonon energy and large band gap in order to lower the attenuation along the transmitting window. Some interesting results have been obtained by adding ionic salts to the covalent telluride glassy matrix. In particular, the GeTe4-AgI system is very promising and effort will be focused on this system in the future 32,35. 3.2 Electrophoretic sensors Alternatively, thanks to the existence of these free charge carriers, telluride glasses display fairly high electrical conductivity while retaining their optical losses at a low level in the mid-infrared 36. These properties enable the development of a new class of sensing probe that can simultaneously act as an electrode and as an infrared collection element. Indeed, the electric behavior of the glass permits to attract charged molecules at the surface of a sensing element in order to collect their infrared signature. Some preliminary tests have been done using telluride glass in the Ge-Te-As system 37. The general electrophoretic set-up is described in figure 6. A voltage is applied between the ITO counter electrode and the glass element in order to generate an electric field that induces the migration of charged molecules. The target molecules are then captured on the surface of the optical element and their infrared signature can be collected.

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Figure 6: a) Attenuated Total Reflection (ATR) Ge-Te-As plate. b) Electrophoretic set-up showing the ATR plate coated by an aluminum layer acting as the cathode. This electrophoretic system has been successfully used to collect bovine serum albumin spectra for example. It has been shown that the biomolecules migrate to the telluride glass plate and that, as expected, the migration rate is a function of the voltage applied between the plate and the ITO layer. Thus, the sensitivity becomes also greater when the voltage increase. More generally, this type of sensing device is particularly useful in bio-sensing experiments because many biological molecules such as viruses, bacteria and protein carry a net surface charge. Thus, figure 7 shows how it is possible to discriminate between two bacteria mixed to each other in the same solution. As seen in the figure 7(b), their spectra are too close to identify them, but thanks to PCA 7(a), the both family of spectra are clearly discriminated.

Figure 7: a) PCA map of 22 bacteria spectra showing the potential for distinguishing different bacterial strains (E. coli and S. aureus) b) the initial related spectra collected thanks to the electrophoretic device described above.

4. CONCLUSION Thanks to their rheological properties, selenide glasses are matchless material to design any devices working in the mid-infrared. The sensitivity of FEWS with selenide glass optical fibers have been demonstrated. Some unsupervised statistical analysis study like Partial Least Squares Regression (PLS-R) or Principle Component Analysis (PCA) have to be implemented to fully validate the potential of these spectroscopic tools. Thus, the efficiency of this whole protocol has been shown in priority in the frame of three health strategic fields of application: food safety, medicine and environment. In the future, the ongoing work of development will be carry by the DIAFIR Company rather than in a strict university environment. In parallel, telluride glass could become more and more interesting for bio-medical sensing. They potentially enable to extend the spectral range of exploration further toward the far infrared. Nevertheless, ongoing works in material science are still needed to stabilize these glasses and to lower their optical losses by increasing their band gap. At this time, telluride glasses are already interesting by exploiting their fairly high electrical conductivity. Thus, some

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electrophoretic sensors are under development. Compare to regular ATR plate, this new class of sensing devices permit to increase drastically the sensitivity of mid-infrared spectroscopy.

ACKNOWLEDGEMENTS The authors thank the French ANR (Emergence, TECSAN, and OPTIC CO2), the ADEME, the European Space Agency, National Science Foundation under Grant Number ECCS-1201865, the CNRS International Associated Laboratory for Materials & Optics and the Partner University Fund for financial grants and supports.

REFERENCES 1. XH Zhang, B Bureau, C Boussard, HL Ma, J Lucas “Glass to see beyond the visible” Chemistry, 14, 432-442

(2008). 2. B Bureau, C Boussard, P Lucas, XH Zhang, J Lucas, “Forming glasses from Se and Te”, Molecules, 9(9),

7398-7411 (2009). 3. N. J. Harrick. Chapter one. IN SONS, W. (Ed.) Internal refection spectroscopy (1967). 4. D.A.C. Compton, S.L. Hill, N.A. Wright, M.A. Druy, J. Piche, W.A. Stevenson, D.W. Vifrine, “in-situ FTIR

analysis of a composite curing reaction using a mid-infrared transmitting optical fibers”. Applied Spectroscopy, 42, 972-979 (1988).

5. J. Heo, M. Rodrigues, S.J. Saggese, G.H. Sigel, Remote fiberoptic chemical sensing using Evanescent Wave interaction in chalcogenide glass fibers, Applied Optics, 30, 3944-3951 (1991).

6. M. Rodrigues Chalcogenide glass fibers for remote spectroscopic chemical sensing. Applied Optics. SPIE (1991).

7. J.S. Sanghera, F.H. Kung, L.E. Busse, P.C. Pureza, I.D. Aggarwal, (1995) Infrared Evanescent absorption spectroscopy of toxic chemicals using chalcogenide glass fibers, Journal of the American Ceramic Society, 78, 2198-2202 (1995).

8. J.S. Sanghera, F.H. Kung, P.C. Pureza, V.Q. Nguyen, R.E. Miklos, I.D. Aggarwal, Infrared Evanescent absorption spectroscopy with chalcogenide glass fibers, Applied Optics, 33, 6315-6322 (1994).

9. O. Eytan, R. Pogreb, S. Sutowski, I. Vasserman, B.A. Seal, A. Katzir, (1999) Fiberoptic evanescent wave spectroscopy (FEWS) for blood diagnosis: the use of polymer coated AgClBr fibers and neural network analysis. Specialty fiber optics for medical applications. San José, SPIE (1999).

10. J. Spielvogel, L. Lobik, I. Nissenkorn, R. Hibst, Y. Gotshal, A. Katzir, Cancer diagnosis using Fourier Transform Fiberoptic Infrared Evanescent Wave Spectroscopy (FTIR-FEWS). IN KATZIR, A. (Ed. Surgical-Assist System. San José, SPIE (1998).

11. J. Spielvogel, R. Hibst, A. Katzir, Monitoring the diffusion of topically applied drugs through human and pig skin using fiber evanescent wave spectrosocpy (FEWS). Specialty fiber optics for medical applications. San Jose, SPIE (1999).

12. M. Katz, I. Schnitzer, A. Bornstein, Quantitative evaluation of chalcogenide glass fiber evanescent wave spectroscopy. Applied optics, 33 (1994).

13. K. Michel, B Bureau, C. Boussard, T. Jouan, J.L. Adam, K.Staubmann, T. Baumann “Monitoring of pollutant in waste water by infrared spectroscopy using chalcogenide glass optical fibers” Sensors and Actuators B-Chemical, 101, 252-259 (2004).

14. K. Michel, B Bureau, C. Pouvreau, J.C. Sangleboeuf, C. Boussard, T. Jouan, T. Rouxel, J.L. Adam, K.Staubmann, H. Steinner, T. Baumann, A. Katzir, J. Bayonna, W. Konz “Development of a chalcogenide glass fiber device for in situ pollutant detection” Journal of Non-Crystalline Solids, 326, 434-438 (2003).

15. D. Le Coq, K. Michel, J. Keirsse, C. Boussard, G. Fonteneau, B. Bureau, J.M. Le Quere, O. Sire, J. Lucas “Infrared glass fibers for in-situ sensing, chemical and biochemical reactions” Comptes Rendus Chimie, 5, 907-913 (2002).

16. ML Anne, E Le Gall La Salle, B Bureau, J. Tristant, F. Brochot, C. Boussard, HL Ma, X Zhang, JL Adam, “polymeristaion of an industrial resin monitored by IR-FEWS” Sensors and actuators B, Vol: 137, Issue: 2, p 687-691 (2009).

17. M.L. Anne, V Monbet, B Bureau, C Boussard, O Loreal, JL Adam, O Sire “Identification of foodborne pathogens within food matrices by IR spectroscopy” sensors and actuators-B, 160, 202-206 (2011).



18. J. Keirsse, C Boussard, O. Loreal, O. Sire, B. Bureau, P. Leroyer, B. Turlin, J. Lucas, “IR optical fiber sensor for biomedical applications” Vibrational Spectroscopy, 32, 23-32 (2003).

19. J. Keirsse, E. Lahaye, A. Bouter, V. Dupont, C. Boussard, B. Bureau, J.L. Adam, V. Monbet, O. Sire “Mapping bacterial surface population physiology in real-time: IR spect. of Proteus mirabilis swarm colonies” App. spect. 60 584-591 (2006).

20. S. Hocdé, O. Loréal, O. Sire, B. Turlin, C. Boussard, D. Lecoq, B. Bureau, G. Fonteneau, C. Pigeon, P. Leroyer, J. Lucas “Biological tissues infrared analysis by chalcogenide glass optical fiber spectroscopy”. IN GANNOT, I., GULYAEV, Y. V., PAPAZOGLOU, T. G. & VANSWOL, C. F. P. (Eds.) Biomonitoring and Endoscopy Technologies (2001).

21. S. Hocdé, O. Loréal, O. Sire, C. Boussard, B. Bureau, B. Turlin, J. Keirsse, P. Leroyer, J. Lucas “Metabolic imaging of tissues by infrared fiber-optic spectroscopy: an efficient tool for medical diagnosis” Journal of Biomedical Optics, 9, 404-407 (2004).

22. P. Lucas, D. LeCoq, C. Junker, J. Collier, D. Boesewetter, C. Boussard, B. Bureau, M. Riley “Evaluation of toxic agent effects on lung cells by fiber evanescent wave spectroscopy” Applied Spectroscopy, 59, 1-9 (2005)

23. M. Riley, D L DeRosa, J Blaine, B G Potter, P. Lucas, D. LeCoq, C. Junker, J. Collier, D. Boesewetter, C. Boussard, B. Bureau “Biologically inspired sensing: Infrared spectroscopic analysis of cell responses to an inhalation health hazard”. Biotechnology Progress, 22, 24-31 (2006).

24. M Riley, P. Lucas, D. Le Coq, C. Juncker, J. Collier, D.E. Boesewetter, D DeRosa, M Katterman, C. Boussard, B. Bureau “Lung cell fiber evanescent wave spectroscopic biosensing of inhalation health hazards” Biotechnology and Bioengineering, 95, 599-612 (2006).

25. ML Anne, C Le Lan, V Monbet, C Boussard-Plédel, M Ropert, O Sire, M Pouchard, C Jard, J Lucas, J L Adam, P Brissot, B Bureau, O Loréal “FEWS using Mid Infrared provides useful fingerprints for metabolic profiling in humans” ML Anne, et al. J. Biomed. Opt. 14, 054033 (2009).

26. A. Seddon, « Mid-infrared (IR) - A hot topic: The potential for using mid-IR light for non-invasive early detection of skin cancer in vivo”, Physica Status Solidi B, 250, 5 1020-1027 (2013).

27. A. Seddon “Potential for using mid-infrared light for non-invasive, early-detection of skin cancers in vivo” Editor(s): Gannot, I, SPIE Conference on Optical Fibers and Sensors for Medical Diagnostics and Treatment, Proceedings of SPIE 8576 (2013).

28. http://www.diafir.com/ 29. P. Jóvári, B. Bureau, I. Kaban, V. Nazabal, B. Beuneu, U. Rütte “The structure of As3Se5Te2 infrared optical

glass”, Journal of Alloys and Compounds 488 (2009) 39–43. 30. G. Delaizir, M. Dussauze, V. Nazabal, P. Lecante, M. Dollé, P. Rozier, E.I. Kamitsos, P. Jovari, B. Bureau

“Structural characterizations of As–Se–Te glasses”, Journal of Alloys and Compounds, Vol 509, Iss 3, 831-836 (2011).

31. B Bureau, S Danto, HL Ma, C Boussard, XH Zhang, J Lucas “Tellurium based glasses a ruthless glass to crystal competition” Solid State Sciences (2008), 10(4), 427-433.

32. Conseil, C; Bastien, JC; Boussard, C; Zhang, XH ; Lucas, P ; Dai, SX ; Lucas, J ; Bureau, B “Te-based chalcohalide glasses for far-infrared optical fiber “OPTICAL MATERIALS EXPRESS Vol 2 Iss 11 1470-1477 2012.

33. A Wilhelm, C Boussard, Q Coulombier, J Lucas, B Bureau, P Lucas “Development of far infrared transmitting Te based glasses suitable for CO2 detection and space optics” Advanced Material, 19, 3796-3800 (2007)

34. S Maurugeon, B. Bureau*, C. Boussard-Plédel, A. J. Faber, P Lucas, X.H. Zhang, J Lucas “Selenium modified GeTe4 based glasses optical fibers for far-infrared sensing” Opt. Material, 33, 4, 660-663 (2011).

35. Wang X; Nie Q; Wang G; Sun J ; Song BA ; Dai SX ; Zhang XH ; Bureau B ; Boussard C ; Conseil, C ; Ma HL “Investigations of Ge-Te-AgI chalcogenide glass for far-infrared application “SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, 86, 586-589 2012.

36. Z. Yang, A. A. Wilhelm, and P. Lucas, “High-conductivity tellurium-based infrared transmitting glasses and their suitability for bio-optical detection,” J. Am. Ceram. Soc. 93, 1941–1944 (2010).

37. Z Yang, M K. Fah, K A. Reynolds, J D. Sexton, ML Anne, M Riley, B Bureau, P Lucas “Opto-electrophoretic detection of bio-molecules using conducting chalcogenide glass sensors”, Optic Express, vol 18, 25 (2010) 26754.



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