Gold-silver bimetallic nanoclusters with enhanced fluorescence for highly selective and sensitive detection of glutathione

Abstract

Herein, a sensitive and selective “off-on” fluorescence sensor for the detection of glutathione (GSH) was fabricated based on Au-Ag bimetallic nanoclusters (NCs) with the assistance of persulfate (S2O82−). The as-prepared Au-Ag bimetallic NCs with enhanced fluorescent intensity about 2.7-folds higher than pure Au NCs was performed due to the synergistic effect of two atoms, which can be quenched by the strong oxidant of S2O82− damaging the structure of Au-Ag bimetallic NCs. However, in the presence of GSH, it can react with S2O82− and induce the restoration of fluorescence. Under optimum conditions, the restored fluorescence ratio was linearly with the concentration of GSH in the range of 1–100 μM and 100 μM–10 mM with a limit of detection of 200 nM. Notably, an IMPLICATION logic gate can be constructed based on this detection system. The proposed logical system for GSH detection is simple, highly sensitive and selective, and has the excellent recovery results for GSH detection in human serum, indicating its promising application in integrated biological detection system.