A water-soluble fluorescent probe for the detection of thiophenols in water samples and in cells imaging

Water pollution is the main cause of death of aquatic organisms such as fish et al. Content of thiophenols in water samples is an important indicator for assessing the degree of water pollution. The development of fluorescent probes with high selectivity and high sensitivity to detect thiophenols in water samples is extremely important in both environmental and life sciences. Although several fluorescent probes for thiophenols detection have been reported in recent years, most of them required the assistance of organic solvents to remedy the restriction caused by the poor water solubility of the probe, which did not fully reflect the actual situation of thiophenols in actual water samples. To fully overcome this shortage, we modified the 1,8-naphthylimide moiety with carboxyl to obtain a water-soluble fluorescent probe which could react with thiophenols specifically through nucleophilic aromatic substitution reaction (SNAr) reaction with turn-on fluorescent responses. The corresponding detection limit was 71 nM. Supported by the spectroscopic changes, test strips based on the probe could detect thiophenols quantificationally and conveniently. At the same time, the probe could detect thiophenols in water sample with quantitative recovery. Besides, cell imaging experiments demonstrated the possibility of the probe to detect thiophenols in living cells. (C) 2018 Elsevier B.V. All rights reserved.