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

Hydrogen sulfide (HS) 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 HS 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 HS. As a result, it exhibits an ultrafast response to HS within only 5 s and demonstrates high absolute fluorescence quantum yield (Φfl) up to 17.63 %. Moreover, DTBH interacts with HS 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 HS over various other analytes. Significantly, the biological imaging investigations in cells demonstrated that DTBH could image endogenous and exogenous HS and provide a promising method for the detection of HS in biological systems.