A novel NIR fluorescent probe targeting mitochondria for the detection of Cys using benzothiocarbonate recognition...

Due to the importance of Cys, the development of methods to detect Cys has become a hot research topic. In the present work, we constructed a novel near-infrared fluorescent probe BP-PTC, which specifically binds Cys with a mitochondria-targeting property, using a synthetic benzopyran salt as a chromophore attached to a phenyl thioformate group. The specific response to Cys is achieved based on the addition-cyclisation-elimination reaction process of Cys with phenyl thioformate, allowing it to exhibit fluorescence emission at 670 nm. In addition, the fluorescence intensity of BP-PTC shows a good linear relationship with Cys in the concentration range of 0 ∼ 28 μΜ. A series of characterization and property tests have demonstrated that BP-PTC has good selectivity and sensitivity for Cys and can be detected by "naked eyes". BP-PTC has been successfully used for the detection of endogenous and exogenous Cys in vivo.