Reaction-based fluorescent turn-on probe for selective detection of thiophenols in aqueous solution and living cells

Abstract

A novel turn-on florescent probe based on a nucleophilic substitution reaction was developed for the detection of thiophenols in aqueous solution and in living cells. In this probe, 10-hydroxyl derivative of coumarin 6H was selected as fluorophore, 2, 4-dinitrophenlate moiety acted simultaneously as recognition unit and fluorophore quencher. This probe features a remarkable large Stokes shift (128 nm) and shows a highly selective detection process for thiophenols with significant fluorescence turn-on response. Notably, biothiols, aliphatic thiols, amino acids and reducing anions do not interfere with the sensing of thiophenols. The probe shows good linearity ranges with low detection limit of 36 nM for thiophenols. More importantly, it was successfully applied for practical detection of thiophenols in real water samples with a good recovery and imaging of thiophenols in living cells, demonstrating its practical application in environmental samples and biological systems.