A Selective and Reversible Fluorescent Probe for Cu 2+ and GSH Detection in Aqueous Environments

摘要

Cu2+ and Biothiols play a critical role in diverse biological processes in organisms. Herein, we reported using a well-known ESPT molecule 2-(2'-Pyridyl)benzimidazol(PBI) as a fluorescent probe to detect Cu2+ and GSH in aqueous solution. PBI presented a rapid fluorescence "ON-OFF" response on Cu2+ over other metal cations, with a low detection limit (39.4 nM), and also been applied in real water samples detection. Through mass spectroscopy, single crystal X-ray diffraction and DFT calculation, we confirmed that two PBI molecules would form a stable complex with one Cu2+. After adding GSH, PBI-Cu2+ complex would release the free probe, and the "on-off-on" recognition process to achieve continuous detection of Cu2+ and GSH.