Dual-functional multi-application probe: Rapid detection of H2S and colorimetric recognition of HSO3− in food and cell

Abstract

Since hydrogen sulfide (H2S) and bisulfite (HSO3−) are widely used in the biological environment and industrial production, many fluorescent probes have been developed to detect them individually. However, designing and synthesizing a sensor that recognizes both H2S and HSO3− remains a challenge. In this study, we developed a new dual-function probe TCF-DNs for the dual channel detection of H2S and HSO3− in EtOH/H2O (2/8, v/v, HEPES 10 mM, pH = 7.4). The color of TCF-DNs changed from lilac to light-blue on treatment with H2S, and a visible color change from lilac to colorless occurred on treatment with HSO3− as well. The easy-to-synthesize TCF-DNs can recognize H2S through rapid near-infrared fluorescence enhancement with a detection limit of 13.5 nM, however, the probe exhibits fluorescence quenching toward HSO3−. The sensing mechanism of TCF-DNs is based on the removal of 2,4-dinitrobenzenesulfonate unit by HS− and the occurrence of a nucleophilic addition for HSO3−. In addition, the application study indicates that probe TCF-DNs can detect HSO3− in granulated sugar, and sensitively detect H2S in red wine, real water, living cells. Meanwhile, TCF-DNs can be used to prepare a cheap test paper strip for the rapid and qualitative detection of H2S by the naked eye and to serve as an indicator to detect H2S gas.