A highly selective and sensitive near-infrared fluorescent probe for imaging of hydrogen sulphide in living cells and mice

Abstract Hydrogen sulphide (H 2 S), the third endogenous gaseous signalling molecule, has attracted attention in biochemical research. The selective detection of H 2 S in living systems is essential for studying its functions. Fluorescence detection methods have become useful tools to explore the physiological roles of H 2 S because of their real-time and non-destructive characteristics. Herein we report a near-infrared fluorescent probe, NIR-HS, capable of tracking H 2 S in living organisms. With high sensitivity, good selectivity and low cytotoxicity, NIR-HS was able to recognize both the exogenous and endogenous H 2 S in living cells. More importantly, it realized the visualization of endogenous H 2 S generated in cells overexpressing cystathionine β-synthase (CBS), one of the enzymes responsible for producing endogenous H 2 S. The probe was also successfully applied to detect both the exogenous and endogenous H 2 S in living mice. The superior sensing properties of the probe render it a valuable research tool in the H 2 S-related medical research.