Combination of hydrophilic quinolinium group and ortho-aldehyde group accelerated thiolysis of dinitrophenyl ether: A colorimetric and turn-on fluorescent probes for the detection of hydrogen sulfide

Small-molecular fluorescent probes are currently being developed for sensing of hydrogen sulfide and are attracted great attention because of the significant roles of H2S in food safety and living organisms. We report herein an efficient approach to modify the previous reported quinolinium-phenol vinylic conjugated fluorescent probes 4NS by combination of the accelerated nucleophilic addition of H2S to an aldehyde group followed by an intramolecular fast thiolysis of dinitrophenyl ether. The modified probe 4ANS can be able to efficient sense H2S and displays typical features, with good selectivity, high sensitivity (LOD = 15 nM), "naked-eye" colorimetric and turn-on fluorescent detection, rapid response time (<3 mins), and good biocompatibility. The mechanism involving thiolysis of dinitrophenyl ether was confirmed by HRMS analysis, and the practical application to detect H2S in food spoilage and cell imaging was successfully demonstrated.