H₂S-Activatable dual-responsive fluorescent probe for bicolor visualization of Ferroptosis and drug-induced liver injury models

Hydrogen sulfide (H 2 S) is a gas with dual roles in both environmental and biological systems. Although it is a natural atmospheric constituent and an enzymatically produced signaling molecule, elevated levels of H 2 S are associated with air pollution, cytotoxicity, and various diseases. Current methods for detecting H₂S are often limited by complex sample preparation, low sensitivity, and inadequate selectivity. To address these challenges, we report the development of a novel dual-channel and dual-responsive fluorescent probe HAR-H₂S , which enables rapid, sensitive, and selective detection of H₂S in both environmental and biological contexts. This probe employs coumarin and naphthalimide derivatives as fluorescent reporters and incorporates dual recognition sites for specific H₂S detection. Upon interaction with H₂S, the probe generates distinct blue and green fluorescent signals, facilitating bicolor imaging. The probe demonstrated excellent selectivity, low detection limits (26.4 nM and 35.1 nM), a relatively large spectral separation (126 nm) and rapid response times (within 3 min). HAR-H 2 S was successfully applied to quantify H 2 S in water samples (tap, river, and lake water) and to image H 2 S in various biological systems, including HeLa cells, HepG2 cells, zebrafish embryos, the ferroptosis model and mouse liver tissue sections. Our results highlight the potential of HAR-H 2 S as a versatile tool for H 2 S detection and imaging in both analytical and biological applications, thereby advancing the field of H 2 S research.