A highly sensitive fluorescent probe for hydrogen sulfide based on dicyanoisophorone and its imaging in living cells

Due to the importance of hydrogen sulfide (H2S) in physiology and pathology, the development of fluorescence probes for the detection of H2S has attracted extensive attention of researchers. We developed a H2S fluorescence probe (DCN-S) based on dicyanoisopentanone using dithioether and ester groups as the reaction sites. Under the nucleophilic substitution of H2S, disulfide bond of DCN-S was broken. Then the probe changed into dicyanoisophorone derivative and emitted an orange fluorescence band from 530 nm to 700 nm (centred 580 nm). Upon response for H2S, DCN-S exhibited high sensitivity (88 nM detection limit) and large stokes shift (155 nm). Importantly, the probe also was successfully used for endogenous and exogenous imaging of living cells.