A SERS study of the molecular structure of alkanethiol monolayers on Ag nanocubes in the presence of aqueous glucose

We report progress towards the surface-enhanced Raman scattering (SERS) characterization of self-assembled monolayers (SAMs) on uniform Ag nanocubes. This study quantifies changes in the SAMs induced by the presence of aqueous glucose. The SAMs were prepared from dodecanethiol and they were representative of highly ordered monolayers as indicated by SERS analysis. We examined the SAMs' response to glucose and observed conformational changes in the alkanethiolate SAMs. Analysis of the trans and gauche bands as well as the C-H stretching modes of the SAMs suggests that the analyte SAM interactions were superficial and there was no penetration for the glucose molecules into the monolayers. (c) 2008 Elsevier B.V. All rights reserved.