A Sensitive and Quick Fluorescent Sensor for the “Turn‐On” Detection and Imaging of Glutathione Based on Sulfur Quantum Dots and MnO2 Nanosheets

ABSTRACT Glutathione (GSH) is one of the most abundant bioethanol antioxidants in living cells. Here, a fluorescent probe based on MnO 2 nanosheets and sulfur quantum dots (SQDs) was fabricated. Because of the synergistic effect of IFE and FRET, the fluorescence from SQDs was quenched by MnO 2 nanosheets. In the presence of GSH, the fluorescence of SQDs could be recovered because of the reduction of MnO 2 nanosheets by GSH. The method can detect GSH in the concentration range of 5 ~ 1000 μM with the detection limit as low as 1.26 μM. This quick, easy, and cost‐effective sensor could be used for the quantification of GSH in serum samples and the imaging of GSH in Escherichia coli O157:H7.