Bioenabled Nanomaterials for Portable Sensing of Food Contamination and Water Pollution

Alan X. Wang1*, and Gregory L. Rorrer2 *wang@eecs.oregonstate.edu

Conclusion

Acknowledgement

Introduction

SERS Characterization

Applications

• Such low cost, bioenabled nanophotonic structures could potentially revolutionize the fabrication of photonic devices for optical communication, biomedical detection, and chemical analysis.

• Diatoms are a group of single-celled photosynthetic algae that make skeletal shells of hydrated amorphous silica, called frustules, which possess hierarchical nanoscale photonic crystal features made by a bottom-up approach at ambient temperature and pressure.

• Due to the coupling between the discrete guided modes of the photonic crystal slab and the radiation continuum above the light line, the bioenabled photonic structure is expected to demonstrate GMR effects with high-Q resonance.

As the nature-created PBG materials, diatoms have been adopted to enhance the optical field of metal nanoparticles on the surfaces of diatom frustules and to increase the sensitivity of surface-enhanced Raman scattering (SERS). Right SEM images shows a single diatom frustule with the zoomed view of the sub-100nm pores. Ag NPs are self-assembled onto the surface of diatom frustules

• The Raman signal intensity is enhanced by 4~6 times on diatom frustule when compared with the flat substrate.

• Bioenabled nanomaterials have demonstrated significant commercial potential as low cost and ultra-sensitive materials for portable sensing

• Optimization of the sensors for specific sensing applications require much more research input

• The authors are currently seeking federal and industry support to develop commercial products

a

1School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, OR, 97331, USA2School of Chemical, Biological & Environmental Engineering, Oregon State University, Corvallis, OR, 97331, USA

Marine Biopolymer Technologies National Institutes of Health (NIH)STTR Phase 2 NSF EFRI-PSBR Office of Naval Research (ONR)

J. Yang, Z. Le, F. Ren, J. Campbell, G. L. Rorrer, A. X. Wang, “Ultra-Sensitive Immunoassay Biosensors using Hybrid Plasmonic-Biosilica Nanostructured Materials,” J. Biophotonics, AcceptedJ. Yang, F. Ren, Z. Le, J. Campbell, G. L. Rorrer, A. X. Wang, "Surface-Enhanced Raman Scattering Immuno-Assay Using Diatom Frustules," IEEE CLEO 2014, STh4H.1, San Jose, CA, June 8-13th, 2014F. Ren, J. Campbell, G. L. Rorrer, and A. X. Wang, "Surface-Enhanced Raman Spectroscopy Sensors from Nano-Biosilica with Self-Assembled Plasmonic Nanoparticles," IEEE Journal of Selected Topics in Quantum Electronics, Special Issue in NanoBiophotonics, 20, 6900806, May/June 2014F. Ren, J. Campbell, X. Wang, G. L. Rorrer, and A. X. Wang, "Enhancing surface plasmon resonances of metallic nanoparticles by diatom biosilica," Opt. Express 21, 15308-15313 (2013), Also appeared as Virtual Journal for Biomedical Optics (VJBO), Vol.8, Issue 8, September 2013F. Ren, J. Campbell, D. Hasan, X. Wang, G. L. Rorrer, A. X. Wang, “Bio-Inspired Plasmonic Sensors by Diatom Frustules,” IEEE CLEO 2013, CTh3I.4, San Jose, CA, June 9-14, (2013)A. X. Wang, G. L. Rorrer, "EMBODIMENTS OF A COMPOSITION COMPRISING DIATOM FRUSTULES AND A METHOD OF USING," U.S. Provisional Application No. 61/759,833

Conventional inspection techniques for food contamination and water pollution: Mass spectrometry (MS) detectors + gas chromatography (GC) or liquid chromatography (LC)Advantage: ultra-sensitiveDisadvantage: complex extraction and purification procedures, dedicated laboratories with expensive equipment and highly-trained personnel

Optical sensing technologies using refractive index sensing or Raman scatteringAdvantage: ultra-sensitive, free of extraction, and fast measurementDisadvantage: expensive sensor devices, complicate testing system

Examples of rationally designed optical sensors for ultra-sensitive chemical and biological detection

Bioenabled Nanomaterials with Unique Photonic Properties --- Photonic Bandgaps (PBGs)

Our Solution of Portable Sensing Technologies

Illustration of photonic crystals with PBGs due to the periodic structure; Optical images of diatoms with different colors due to the reflection from the PBGs; Preparation of a dense layer of diatom frustules by microbiological incubation

Illustration of using the bioenabled nanomaterials with portable Raman spectrometers for (a) spot-inspection of food contamination, and (b) high throughput in-situ screening of organic compounds in water.

What can be sensed?• Food contaminants: benzyl butyl phthalate (BBP), melamine,

pesticide, etc.• Water pollutants: aromatic compounds, such as benzene, phenol,

chlorobenzene, pyrocatedchol, etc.• Air pollutants: volatile organic chemicals, such as Acetone, Benzene,

Ethylene glycol, Formaldehyde, Methylene chloride, Perchloroethylene, Toluene, Xylene, and 1,3-butadiene

Who will need the sensors?• Food distribution industry such as Marshfield Food Safety, Certified

Laboratories, Inc., and ABC Research Laboratories• FDA and FSIS (a subcomponent of the USDA) inspectors • Federal, state, and local government agencies such as EPA, Oregon

Water Resources Department, City of Corvallis, Oregon Department of Fish and Wildlife, and Oregon Department of Agriculture

• Oil and gas companies to prevent water pollution and environmental damage

• Environmental, geographical, agricultural, and biological researchers in universities or other institutes