The chemiluminescence of AgInS2 quantum dots and its application as a sensing platform for glutathione assay

Herein, we prepared highly luminescent water-soluble AgInS2 quantum dots (AIS QDs) by a green and simple hydrothermal method and characterized them by various spectroscopic and microscopic techniques. The chemiluminescence (CL) of AIS QDs induced by direct chemical oxidation was investigated. It was found that NaIO4 in alkaline solution elicits a remarkable CL from these QDs. The CL was proved to be originated from the excited-state QDs, produced during the reaction. Further studies revealed that the addition of glutathione (GSH) to NaIO4-AIS QDs system effectively increased the CL intensity. This was employed as a sensing platform for sensitive assay of GSH. In the optimized conditions, the relation between the CL intensity and GSH concentration was linear in the range of 1.0 x 10(-9) mol L-1 to 5.0 x 10(-6) mol L-1 with a detection limit of 2.8 x 10(-10) mol L-1. To evaluate the practical usefulness of the assay, the established technique was applied to the analysis of human plasma.

Automated summary

Highly luminescent water-soluble AgInS2 quantum dots were prepared through a green hydrothermal method, and their chemiluminescence induced by NaIO4 in alkaline solution was investigated. The addition of glutathione effectively enhanced the luminescence intensity, providing a sensing platform for sensitive assay of GSH with a linear range from 1.0 x 10(-9) mol L-1 to 5.0 x 10(-6) mol L-1 and a detection limit of 2.8 x 10(-10) mol L-1, which was successfully applied to the analysis of human plasma for practical use.