The design of hydrogen sulfide fluorescence probe based on dual nucleophilic reaction and its application for bioimaging.

Hydrogen sulfide (H2S) can undergo dual nucleophilic reaction, which is a wise and effective way to distinguish biothiols and H2S. A novel H2S fluorescence probe, 4-{2-[4-(2-disulfide pyridyl-benzoyloxy)-phenyl]-vinyl}-1-methyl-pyridinium[e]iodide (DSPBP), with two nucleophilic reaction sites has been developed. The spectra results showed that DSPBP could detect H2S in ratiometric and colorimetric signals and has excellent selectivity and sensitivity. The fluorescence ratiometric signals (F520/F450) displayed a prominent increase from 0.74 to 7.08, the fluorescence color turned to yellow form blue simultaneously. The linear range was 2-14 μM and its detection limit was 25.7 nM. Moreover, the biocompatibility of DSPBP was fine and its toxicity was very low. It has been successfully used for imaging H2S in cells.