A Highly Selective Fluorescent Probe for Imaging Hydrogen Sulfide in Living HeLa Cells

As an important endogenous gasotransmitter, hydrogen sulfide (H₂S) has been implicated with a variety of biological processes and has attracted more and more attention for its key role in a wide range of pathological processes. However, lacking tools for H₂S-specific in situ detection, the changes of endogenous H₂S levels in the pathological progression of diseases are still unclear. In this work, a turn-on fluorescent probe (BF₂-DBS) has been designed and synthesized by two-step reactions using 4-diethylaminosalicylaldehyde and 1,4-dimethylpyridinium iodide as raw materials. Probe BF₂-DBS displays high selectivity and sensitivity to H₂S with a large Stokes shift and good anti-interference ability. The practical application of probe BF₂-DBS to detect endogenous H₂S was evaluated in living HeLa cells.