A New and Reproducible Surface-Enhanced Resonance Raman Scattering Method for the Determination of Trace Au(III) in Solution Using 4-Mercaptopyridine as Molecular Probe

Abstract

In pH 6.5 Na2HPO4-NaH2PO4 buffer solution and in the presence of stable reagent PEG10000 and aggregation reagent NaCl, nanosilvers were aggregated to form stable aggregated-nanosilvers (ANS). The molecular probe of 4-mercaptopyridine (MP) adsorbed on the surface of ANS to form MP-ANS conjugates that produce strongest surface-enhanced resonance Raman scattering (SERRS) peak at 1097 cm-1. When Au(III) was added, the SERRS intensity at 1097 cm-1 decreased. The decreased SERRS intensity was linear to Au(III) concentration in the range of 5-50 ×10-10 mol/L, with a detection limit of 2.0×10-10 mol/L Au(III).