Highly sensitive and selective coumarin probe for hydrogen sulfide imaging in living cells

Hydrogen sulfide (H2S) is the third endogenous gasotransmitter, following nitric oxide (NO) and carbon monoxide (CO). Efficient methods for selective monitoring H2S in biological systems are significant. In this study, we designed and synthesized a new coumarin-based probe DNPOCA for H2S with colorimetric and fluorescent dual signaling. In this probe, 7-hydroxycoumarin-4-acetic acid methyl ester was employed as a fluorophore and a dinitrophenyl (DNP) ether moiety was used as the recognition unit. The H2S probe exhibited excellent selectivity and high sensitivity with a detection limit as low as 49.7 nM. The cytotoxicity assay showed that DNPOCA possessed a low effect on cell viability. Furthermore, DNPOCA could be successfully applied for H2S imaging in living cells.