Synthesis of p-aminothiophenol-embedded gold/silver core-shell nanostructures as novel SERS tags for biosensing applications.

We describe a novel surface-enhanced Raman scattering (SERS) tag that is based on Au/Ag core-shell nanostructures embedded with p-aminothiophenol. The Au/Ag core-shell sandwich nanostructures demonstrate bright and dark stripe structure and possess very strong SERS activity. Under optimum conditions, the maximum SERS signal was obtained with a 10 nm thick Ag nanoshell, and the enhancement factor is 3.4 × 10 at 1077 cm. After conjugation to the antibody of muramidase releasing protein (MRP), the Au/Ag core-shell nanostructures were successfully applied to an SERS-based detection scheme for MRP based on a sandwich type of immunoassay. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]