Sensitive detection of glutathione through inhibiting quenching of copper nanoclusters fluorescence

A method for a sensitive fluorescence detection of glutathione was established. Glutathione-stabilized copper nanoclusters (CuNCs) were synthesized via a facile process. These CuNCs showed blue fluorescence with a peak around 450 nm. In the presence of p-benzoquinone (PBQ), the electron transfer from the copper nanoclusters to PBQ quenched the fluorescence of the CuNCs. Glutathione (GSH), as a reducing agent, formed a complex with PBQ. This formation inhibited the quenching from PBQ and a restored fluorescence was obtained. This interaction provided a fluorescence enhancement for the measurement of GSH. Under the optimal condition, linear responses were obtained toward GSH in the ranges of 0.06-6.0 mu M, with a limit of detection at 20 nM. This developed assay was easy in operation with high sensitivity and selectivity. The applicability was approved with successful glutathione measurements in real samples. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A sensitive fluorescence detection method for glutathione was developed using glutathione-stabilized copper nanoclusters. The interaction between CuNCs and p-benzoquinone provided fluorescence enhancement for glutathione measurement. The assay showed high sensitivity and selectivity, with successful application in real sample measurements.