Improved surface-enhanced Raman scattering of insulin fibril templated colloidal gold nanoparticles on silicon

Insulin fibrils were used as a biotemplate to attach gold nanoparticles to silicon wafer surfaces for application as surface-enhanced Raman scattering (SERS) substrates. Gold nanoparticles (NP) attach to the insulin fibrils through electrostatic interactions forming chains of discreet NPs. A combination of 4-aminothiophenol and 4-Mercaptobenzoic acid were used as probe molecules to evaluate the Raman signal enhancement that was 10(4) to 10(6). The SERS signal was strongly enhanced on these surfaces due to the close inter-particle spacing of the patterned gold NPs. c 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.JNP.6.063501]