Preparation of near-infrared Ag2S quantum dots for detection of bisphenol A in water

The work develops a novel method for the detection of bisphenol A (BPA) based on glutathione (GSH)-protected silver sulphide quantum dots (Ag2S QDs), which was simple, fast, non-toxic, sensitive and selective. Ag2S QDs were synthesised with a sulphur-hydrazine hydrate complex as the S2- source and GSH as the stabiliser. Ag2S QDs, near-infrared QDs, offered the advantages over lower background fluorescence and lower signal loss. The fluorescence peak of Ag2S QDs at 650 nm was quenched significantly in the presence of BPA. Good linear correlations were obtained over the concentration range from 0 to 60 M of BPA under optimised conditions. The developed selective and sensitive method presaged more opportunities for the application in environmental samples.