AIE fluorescent bio-probe for recognition of exogenous and endogenous H2S signaling molecules, and targeted detection of nonalcoholic fatty liver.

Hydrogen sulfide (H₂S) has attracted attention as a harmful substance causing ecological pollution. However, due to the lack of H2S specific detection tools, the changes in endogenous hydrogen sulfide levels during the pathological progression of chronic liver disease are not fully understood. In this study, a novel aggregation induced emission (AIE) fluorescent bio-probe HBA was developed to facilitate high-selective detection of exogenous and endogenous H2S. HBA showed strong water solubility, high selectivity, low detection limit (0.45 nM), rapid responsiveness, high fluorescence quantum yield (18.51%) and low cytotoxicity, and produces a strong fluorescence. Multiple mechanistic experiments demonstrated that the bio-probe undergoes cyclization reaction with H2S, inducing fluorescence quenching followed by the appearance of a bright yellow color turning colorless. In this study, we leveraged this feature of HBA to detect the H2S content in real water samples and food (fish, pork, and shrimp) during the spoilage process. In addition, HepG2 cells and zebrafish embryos were imaged, later Oil Red and H&E staining were performed on the constructed NAFLD mouse model. Furthermore, the biological imaging of mice was achieved, demonstrating that the bio-probe HBA may be a powerful tool for detecting endogenous H2S in fatty liver in clinical diagnosis and environment detection.