A turn-on fluorescent probe based on 2,4-dinitrosulfonyl functional group and its application for bioimaging

Herein we report a highly selective thiol-reactive fluorescent probe based on a nucleophilic substitution reaction for detecting thiols over other relevant biological species. The probe, triphenylamine as a fluorophore and 2,4-dinitrobenzenesulfonyl chloride as a nucleophilic substitution group was synthesized and characterized. The ability to specially recognizing thiol was investigated by UV-vis and fluorescence spectrometers. Among the tested amino acids, only Cys, Hcy and GSH could turn on the fluorescence emission. It suggested that the system was a highly selective sensor for thiols. More importantly, the compound features a good linearity range and the detection limit is as low as 10(-8) mol/L. In addition, as a typical biological thiol, the ability of probe to detecting Cys in living cells (HepG2 cells) via an enhancement of the fluorescence was proved. (C) 2016 Elsevier B.V. All rights reserved.