Visual Tracking of Hydrogen Sulfide: Application of a Novel Lysosome-Targeted Fluorescent Probe for Bioimaging and Food Safety Assessment.

The equilibrium state of hydrogen sulfide (HS), a gaseous signaling molecule produced by lysosomal metabolites, in vivo is crucial for cellular function. Abnormal fluctuations in HS concentration can interfere with the normal function of lysosomes, which has been closely linked to the pathogenesis of a variety of diseases. In view of this, a novel fluorescent probe based on 1,3,5-triarylpyrazolines was developed for the precise detection of HS in lysosomes by using the hydrophilic morpholine moiety as a lysosomal targeting unit, and 2,4-dinitroanisole as a fluorescence-quenching and HS-responsive unit. The probe cleverly combines the advantages of simple synthesis, sensitive blue fluorescence turn-on with a limit of detection, LOD, of 97.3 nM, good stability, and fast response time (10 min), which makes successful in portable monitoring of meat freshness in the form of test strips. Moreover, the excellent biocompatibility and precise targeting capability of the probe make it perform well in the monitoring of HS in lysosomes, living cells, and zebrafish. This work not only provides new technical tools for food quality control but also paves up new ideas for early diagnosis and treatment of HS-related diseases.