A single fluorescent probe for one- and two-photon imaging hydrogen sulfide and hydrogen polysulfides with different fluorescence signals

Reactive sulfur species (RSS), primarily containing glutathione (GSH), cysteine (Cys), hydrogen sulfide (H2S) and hydrogen polysulfides (H2Sn, n > 1), were crucial endogenous biological signal molecules. Among them, H2S and H2Sn played extremely momentous roles in many physiological and pathological processes. Limited by the vivo environmental diversity and complexity, it was highly desirable to rely on the single fluorescence probe platform to visualize H2Sn and H2S according different fluorescence signals. Herein, we reported a two-photon excited fluorescent probe MC-S-n that had the following merits: (I) ratiometric and colorimetric: reducing detection errors and conducting visual analysis; (II) two-photon microscope: better performance in vivo and vitro imaging; (III) two specific sulfide reaction sites: studying on the mutual transformation of H2Sn and H2S in biological systems. Furthermore, take advantages of low cytotoxicity (cell viability >= 85.99%), low limit of detection (21 nM), significant photostability, excellent pH stability, quick response behavior (175 s) and high penetration depth (110 mu m), MC-S-n can be employed to visualize endogenous and exogenous H2Sn and H2S in cells, liver tissues and zebrafish.