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

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.