A two-layer gold surface is developed for use with surface-enhanced infrared absorption spectroscopy (SEIRAS) consisting of a conducting underlayer onto which Au nanoparticles (AuNPs) are grown by self-catalyzed electroless deposition. AuNPs are grown on protruding substructures of the 25 nm thin underlayer. The enhancement factor of the two-layer gold surface is controlled by the growth conditions. Cytochrome c adsorbed to a self-assembled monolayer of mercaptoethanol is used as a reference system. Under optimum conditions the absorbance of the amide I band is increased by a factor of 5 versus the classical SEIRAS surface. Reversible reduction/oxidation of cytochrome c on the two-layer gold surface is shown to take place by cyclic voltammetry.
Vol. 4, Iss. 11 Virtual Journal for Biomedical Optics
C. Nowak, C. Luening, W. Knoll, and R. L. C. Naumann, "A Two-Layer Gold Surface with Improved Surface Enhancement for Spectro-Electrochemistry Using Surface-Enhanced Infrared Absorption Spectroscopy," Appl. Spectrosc. 63, 1068-1074 (2009)