A dynamic thiol-disulfide exchange assisted high cell-penetrating fluorescent probe for intracellular H2S detection

Hydrogen sulfide (H2S) is a gaseous signaling transmitter which plays a crucial role in cell fates. Given the volatility of H2S in live cells corresponding to the various cell activities, it is important to design and synthesize novel fluorescent probes which could enter cells rapidly for the fast H2S detection. Herein, we reported a turn-on fluorescent probe P1 for H2S labeling in live cells, based on the dynamic thiol-disulfide exchange mechanism on cell surface, which facilitated the probe to enter cells quickly. High performance liquid chromatography (HPLC) results indicated the decoration of cell-penetrating disulfides endowed P1 with a high cellular uptake efficiency. Fluorescence microscopic imaging for HeLa cells suggested P1 was competent for intracellular H2S detection at submicromolar level. We expected our simple but effect strategy which enhanced the cell permeability of probes to benefit more accurate detection for intracellular specific molecule.