A turn-on fluorescence probe for hydrogen sulfide in absolute aqueous solution.

A turn-on hydrogen sulfide (H2S) fluorescence probe, 4-{2-[4-(2,4-dinitrophenoxy)-phenyl]-vinyl}-1-methyl-pyridinium iodide (DPPVP), based on the thiolysis reaction of dinitrophenyl ethers (DNP) has been proposed. Pyridinium structure enhanced the water solubility of DPPVP, which could quickly respond to H2S in absolute PBS solution and the fluorescence spectra of DPPVP at 520 nm were turned on by H2S. The spectra results exhibited that DPPVP could sensitively detect H2S with satisfied linear range (0-40 μM) and detection limit (13.4 nM). The high selectivity for H2S against biothiols was attributed to the significant difference in the pKa and the molecular size. Moreover, DPPVP has been successfully used for detecting H2S in vegetable.