A phenothiazine-based turn-on fluorescent probe for the selective detection of hydrogen sulfide in food, live cells and animals

In this work, a phenothiazine-based fluorescent probe (PR) has been developed for the selective detection of hydrogen sulfide (H2S) in biosystems and monitoring H2S produced in the food spoilage process. The nucleophilic attack of H2S on the CC double bond of PRvia a Michael addition interdicted the ICT process to trigger 34-fold enhancement of the fluorescence emission. PR featured high selectivity and sensitivity (1.8 μM), low cytotoxicity and reliability at physiological pH. "Naked-eye" monitoring of H2S produced in the food spoilage process using PR was successfully accomplished. The preliminary fluorescence imaging studies showed that PR is suitable for the visualization of exogenous and endogenous H2S in living cells and live animals. Moreover, PR has been successfully applied to the visualization of H2S generation in an inflammation model. The results indicated that PR is an effective tool to monitor H2S production in the fields of biomedicine and food safety.