Bimetallic Au/Ag nanoframes as spectator for Co2+ ion

A highly sensitive colorimetric sensing methodology based on glutathione (GSH)-modified silver nanoparticles (AgNP) for the selective analysis for Co2+ ions is reported. We attempted to enhance the chemical stability of AgNPs in low pH condition by additional treatments such as sulfidation and galvanic replacement reaction (GRR). Bimetallic Au/Ag nanoframes (Au/AgNF) with center-open nanostructures were prepared via GRR, and the selective detection of Co2+ ion was evaluated at various concentrations. GSH-Au/AgNF has good linearity between concentration of Coe' ion and absorbance intensity in UV-vis spectra, and thus allows a rapidly quantitative assay of Co2+ down to 1.7 mu M.(C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.