Comparative SERS and in situ ATR-FTIR study of protein/Ag nanoparticle multilayers

COLL 154

Melek Erol, merol1@stevens.edu1, Henry Du, hdu@stevens.edu2, and Svetlana A. Sukhishvili, ssukhish@stevens.edu1. (1) Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030, (2) Department of chemical, biomedical and materials engineering, Stevens Institute of Technology, Castle point on hudson, Hoboken, NJ 07030
We present strategies for construction of protein/Ag nanoparticle multilayers on planar silicon substrates as well as on silica microspheres using layer-by-layer self-assembly of proteins such as lysozyme, avidin and concanavalin A, and negatively charged Ag nanoparticles. Stepwise growth of multilayers on silica microspheres resulted in reversal of sign of zeta potential of silica microspheres. Deposition of Ag nanoparticles within multilayers was also confirmed by SEM. A combination of in situ ATR-FTIR and SERS techniques enabled a comparative study of total amount of protein adsorbed within protein/nanoparticle films, and the nature of the interface between protein and Ag nanoparticles. We discuss the opportunities of this multilayer approach for SERS-based label-free detection of biomolecules at surfaces, with specific examples of avidin/biotin and concanavalin A/glucose pairs.
 

Fundamental Research in Colloid and Surface Chemistry
6:00 PM-8:00 PM, Monday, August 20, 2007 BCEC -- East Registration, Poster

Division of Colloid & Surface Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007