ESIPT Fluorescence Probe Based on Double-Switch Recognition Mechanism for Selective and Rapid Detection of Hydrogen Sulfide in Living Cells

A novel fluorescence probe, HBTSeSe, was designed and synthesized for the detection of H2S with a double-switch mechanism of a broken diselenide bond followed by thiolysis of ether. Then, 2-(2'-hydroxyphenyl) benzothiazole (HBT) was released as fluorophore, which has large Stokes shift based on the excited state intramolecular proton transfer process. The probe responded selectively and rapidly to H2S, with the fluorescence increased by 47-fold immediately after the addition of H2S. HBTSeSe was able to detect H2S in the cytoplasm, specifically in cell imaging experiments. The results also showed that H2S was produced in the immune response of RAW264.7 cells activated by phorbol-12-myristate-13-acetate