An “off−on” NIR fluorescence probe for visualization of H2S in food spoilage, living cells and zebrafish

Hydrogen sulfide (H2S), a significant substance, could cause food safety problems and damage to organisms. Consequently, it is critical to develop an effective fluorescence sensing strategy that can measure H2S in both food samples and biological systems with superior selectivity and sensitivity. Herein, a simple H2S-activatable near-infrared (NIR) fluorescence probe (FC-HS) based on a coumarin–benzopyrylium scaffold and bearing a 2,4-dinitrophenyl moiety was built and structurally characterized, exhibiting a remarkable NIR fluorescence response for H2S at 660 nm with a low limit of detection (LOD = 35.7 nM) despite the presence of other possible interference species. Meanwhile, the FC-HS mounted on the filter paper strips, was capable of successfully detecting H2S gas produced by food spoilage. Moreover, FC-HS could also monitor H2S in living cells and zebrafish with excellent biocompatibility and low cytotoxicity.