Rapid detection of hydrogen sulfide utilizing dinitrophenyl ether-based fluorescent probes incorporating aldehyde...

Hydrogen sulfide (H₂S) plays a crucial role in the regulation of various physiological processes within living organisms, including cell signaling, vascular tone modulation, and the inflammatory response. The real-time detection and visualization of H₂S levels in practical samples hold significant importance for biological analysis. In this study, 3-(benzo[d]thiazol-2-yl)-5-bromo-2-(2,4-dinitrophenoxy)benzaldehyde (DTBH) was designed and synthesized based on the mechanism of excited state intramolecular proton transfer (ESIPT). The probe employs a 2,4-dinitrophenyl ether with an ortho-aldehyde group as the reaction site to test H₂S. As a result, it exhibits an ultrafast response to H₂S within only 5 s and demonstrates high absolute fluorescence quantum yield (Φfl) up to 17.63 %. Moreover, DTBH interacts with H₂S to release its precursor DTB, which leads to a marked enhancement in fluorescence emission with 542 nm. DTBH shows high sensitivity and excellent selectivity for H₂S over various other analytes. Significantly, the biological imaging investigations in cells demonstrated that DTBH could image endogenous and exogenous H₂S and provide a promising method for the detection of H₂S in biological systems.