Detection of ag+ and cysteine using rapid synthesis of copper nanoclusters with dual ligands

In this work, the copper nanoclusters with red fluorescence (CuNCs@DAMP) were prepared with 4,6-diamino-2-mercaptopyrimidine (DAMP) as a ligand by a simple one-pot method, but the CuNCs@DAMP couldn't respond to silver ions (Ag + ) and L-cysteine (Cys). Then glutathione (GSH) modified CuNCs@DAMP (GSH-CuNCs@DAMP) with short preparation time (10 min) was found that not only its maximum emission peak underwent a significant blue-shift (from 705 to 605 nm), but also it could selectively detect Ag + and Cys with LOD (limit of detection) of 0.018 and 0.19 μM and the linear ranges of 0.05–10.0 and 0.6–73.0 μM. Meanwhile, the synthetic conditions of GSH-CuNCs@DAMP and the fluorescence quenching mechanisms of GSH-CuNCs@DAMP by Ag + and Cys were studied intensively. Furthermore, the CuNCs was successfully employed to monitor Ag + and Cys in real samples with good recoveries, which hinted that a simple, fast and sensitive method was provided for Ag + and Cys assays.