An effective HBT/indanone-based fluorescent probe for cysteine detection in cells

The abnormality of Cys concentration in organism could lead to a series of diseases, so its effective detection is of great importance in disease diagnosis. Here we developed a novel ESIPT fluorescent probe HBT-IDAc based on the classic ESIPT fluorophore 2-(2′-hydroxyphenyl)benzothiazole (HBT) and indanone, which could selectively and sensitively detect Cys with a large Stokes shift up to 210 nm and the detection limit to 0.89 μM. In addition, the probe exhibited good anti-interference and low cytotoxicity, and has been successfully applied to monitor Cys in cells. •A novel ESIPT fluorescent probe for selective and sensitive detection of Cys was developed.•The probe has the large stokes shift (210 nm) and good LOD (0.89 μM) in aqueous environment.•The probe exhibits low cytotoxicity and has been applied for imaging Cys in cells.