Modulation of fluorescence sensing properties of coumarin-based fluorescent probe for H2S and its application in cell imaging.

A coumarin-based turn on probe, named 3-((E)-3-(1H-indol-3-yl)acryloyl)-2H-chromen-2-one(IAC) was designed and synthesized for the detection of H2S in aqueous medium. IAC showed no obvious red fluorescence in Tris-HCl(pH = 7.2, 60% DMF), a 28.2-fold fluorescence enhancement was found when 40 equiv. H2S was added. Other analytes such as anions, metal ions and GSH, Cys, Gly did no significant fluorescence enhancement at 580 nm to IAC. The red fluorescence enhancement mechanism between IAC and H2S was considered by DFT and ESI-MS. Overall, IAC was successfully applied in cell imaging.