A coumarin-based “off–on” fluorescent probe for highly selective detection of hydrogen sulfide and imaging in living cells

Hydrogen sulfide (H2S), as a significant signaling molecule, is associated with diverse physiological and pathological processes. However, it's still a challenge to explore outstanding tools for detecting endogenous H2S in vivo. Thus, a simple "off-on" H2S fluorescent probe CMHS has been reasonably designed, and it is based on coumarin as the fluorophore group. The probe CMHS displayed a crucial turn-on fluorescence enhancement (180-fold), rapid reaction time, high selectivity, and a low limit of detection (2.31 × 10-7 M). Additionally, probe CMHS could be applied to visualize exogenous and endogenous H2S successfully in HeLa cells with low cytotoxicity and good permeability.