Fluorescence/Colorimetric Dual-Mode Probe Based on Nitrogen, Sulfur, and Boron Codoped MXene Quantum Dots for...

Quantifying and monitoring glutathione (GSH) in living cells is of great significance for understanding GSH-related oxidative stress disorders and neoplastic conditions. In this work, we developed nitrogen/sulfur/boron codoped MXene quantum dots (NSB-MQDs) through a facile single-pot hydrothermal synthesis strategy for fluorescence/colorimetric detection and imaging of GSH. The fluorescence "Turn-On" sensing signal was generated by the electron or energy transfer process between GSH and NSB-MQDs, which exhibited a fluorescence quenching phenomenon with the increase of GSH. Meanwhile, the GSH-induced aggregation of NSB-MQDs generated a concentration-dependent hypochromic shift from yellow to pink. The analytical probe performed satisfactorily for GSH detection in the range of 50-325 μM with a low detection limit of 0.978 μM, and this sensing probe has been successfully applied to the detection of GSH in real samples. Furthermore, this dual-mode probe enables in situ imaging and monitoring of mitochondrial GSH with low cytotoxicity in living cells and zebrafish. The developed strategy not only provides insights into MXene-based nanoprobe engineering but also demonstrates a broad application prospect for the early diagnosis of diseases and biochemical imaging.