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SERS-based Biosensors

SERS-based Biosensors. James Krier, Lalitha Muthusubramaniam Kevin Wang, Douglas Detert Final Presentation EE235: Nanofabrication May 12, 2009. Overview. Technology Landscape: Optical techniques for biosensing Surfaced-enhanced Raman scattering ( SERS ) Technical background

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SERS-based Biosensors

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  1. SERS-based Biosensors James Krier, Lalitha Muthusubramaniam Kevin Wang, Douglas Detert Final Presentation EE235: Nanofabrication May 12, 2009

  2. Overview • Technology Landscape: Optical techniques for biosensing • Surfaced-enhanced Raman scattering (SERS) • Technical background • SERS-based biosensors • Financial and market considerations of SERS

  3. Vast Technology Landscape Diverse Applications

  4. Total internal reflectance fluorescence (TIRF) biosensor TIR Evanescent wave http://www.microscopyu.com/articles/fluorescence/tirf/tirfintro.html

  5. Epifluorescence TIRF Typical TIRF Sensogram Advantages High Signal to noise ratio (very little secondary emission from bulk solution) Highly robust, low cost, portable Drawbacks Need for labels High cross-reactivity (hence not easy to multiplex) http://www.tirftechnologies.com/principles.php

  6. Molecularly Imprinted Polymers as Optical Sensors Schematic representation of molecular imprinting Distribution of binding affinities in MIP vs. Ab Chemical Reviews, Chem. Rev.,100 2495 (2000)

  7. 3 methods to monitor binding in MIPs • Direct monitoring of analyte in solution; Incorporation of spectroscopically responsive monomers into the matrix;Competition assays using labeled ligands Polymer International, Vol 56( (4), pp. 482-488

  8. Reflectometric interference spectroscopy (RIFS) • The reflected beams superimpose and change optical thickness of the transducer by binding events onto the surface. Shift in characteristic interference spectrum is transformed into a signal curve. J. Immunological Methods Vol 292, Issues 1-2, September 2004, pp.35-42

  9. Reflectometric interference spectroscopy (RIFS) Protein concentration determined spectrophotometrically and active antibody concentration determined by biosensor and ELISA for 9 sequentially eluted fractions. J. Immunological Methods Vol 292, Issues 1-2, September 2004, pp.35-42

  10. The SERS Solution Adsorption Excitation Detection

  11. Raman Spectroscopy C.V. Raman http://www.kamat.com/database/content/pen_ink_portraits/c_v_raman.htm Adapted from http://upload.wikimedia.org/wikipedia/commons/8/87/Raman_energy_levels.jpg

  12. adenine cytosine guanine thymine uracil Raman Spectroscopy • Selection rules • Based on symmetry elements of polarizability tensor • Vibrational fingerprint • Comprised of narrow spectral features • Robust mechanism • Not subject to photobleaching • Weak Signal • Compared to Rayleigh scattering / fluorescence Provides rich info. about structural data! Gelder, et al., J. Raman Spectrosc., 38 1133 (2007) A. Campion et al., Chem. Soc. Rev.,27 241 (1998)

  13. Surface-Enhanced Raman Scattering M. Fleischmann, et al., Chem. Phys. Lett., 26 163 (1974) D.L. Jeanmaire, R.P. Van Duyne, J. Electroanal. Chem., 84 1 (1977) M.G. Albrecht, J. A. Creighton, J. Am. Chem. Soc., 99 15 (1977) S. Schultz, et al., Surface Science,104 419 (1981) M. Moskovits, , Reviews of Modern Physics, 57 3 (1985) K. Kneipp, et al., Chem. Rev., 99 2957 (1999)

  14. Away from plasmon resonance At plasmon resonance SERS Enhancement • Chemical Enhancement • Based on metal-molecule charge-transfer effects • Electromagnetic enhancement • Coupled to surface plasmon excitation of metal nanostructures Tunable resonances: Shape- and Size-effects A.J. Haes, et al., Anal. Bioannal. Chem., 379 920 (2004) S. A. Maier, et al., Adv. Mater., 13 1501 (2001)

  15. 10-250 nm SERS Enhancement Enhancing SERS substrates • Plasmon resonance leads to local field enhancement near the surface • Adsorbed molecules see increased field • Raman signal enhancement (up to 1015) • Depends on local geometry of adsorption site K. Kneipp, et al., Chem. Rev., 99 2957(1999) J. Aizpurua, et al., Phys. Rev. Lett., 90 057401-1 (2003)

  16. 1500 cm-1 1532cm-1 1600cm-1 1635cm-1 The SERS Advantage • Molecular fingerprinting • Unique vibrational spectra distinguishes molecules • Tagless biosensing • Fluorescent dyes are not needed • Multiplexed sensing • Plasmon resonances allow for sensor tunability • In vivo applicability • Near-IR excitation and biocompatability allow • Femtomolar and beyond • Single molecule spectroscopy is possible S.M. Nie, et al., Science, 275 1102 (1997) http://www.oxonica.com/diagnostics/diagnostics_sers_imaging_applications.php

  17. Single Molecule Detection PRL 78, 1667 (1997)

  18. TERS nanowerk.com

  19. TERS Faraday Discuss., 132, 9 (2006)

  20. TOPOGRAPHY + SPECTROSCOPY PRL 100, 236101 (2008)

  21. In-vivo glucose sensing Faraday Discuss., 132, 9 (2006)

  22. Other Options PRL 62, 2535 (1989).

  23. More Moerner et al. Nature 402, 491 (2000).

  24. stanford.edu/group/moerner/sms_movies.html

  25. NSOM JPC 100, 13103 (1996)

  26. SERS Market • Consumables $50 to $750 per analysis $1 million market annually • Instrumentation $10,000 - $180,000 Image source: http://senseable.mit.edu/nyte/visuals.html (New York Talk Exchange) Numbers: http://www.thefreelibrary.com/Market+profile:+SERS-a0137966471

  27. SERS Companies • Bruker Optics • D3 Technologies (Mesophotonics) • Oxonica • Renishaw • Real Time Analyzers http://www.brukeroptics.com/raman.html

  28. SERS Vials • Real Time Analyzers • Sol-gel of Au or Ag nanoparticles • 106 signal enhancement www.rta.biz

  29. Portable Raman • Real Time Analyzers RamanID • DeltaNu Inspector Raman Diesel Fuel Spectrum

  30. SPR Companies • Biacore (GE) • Biosensing Instrument • FujiFilms • GWC Technologies • Ibis • Sensiq

  31. SPR Analyzer • Biosensing Instrument BI-2000 • Cost: $39k • Liquid/Gas Detection • 10-4 degree sensitivity

  32. Cost Comparison

  33. Conclusion: SERS • Even simple (diatomic) molecules can have complex and reproducible vibrational fingerprints • The most practical option for sensing near the single-molecule level for a variety of analytes in solution or air, lending to an array of applications ranging from trace gas detection to automated protein identification • Easy to couple with other supplementary techniques (e.g., AFM) • Provides an economically feasible sensing mechanism for portable devices in atmospheric conditions

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