A coumarin-based fluorescent probe for hypochlorite ion detection in environmental water samples and living cells

In this study, we developed a new fluorescent probe (CMM) based on coumarin dye and malononitrile, for highly sensitive and selective detection of hypochlorite ion (ClO-). CMM showed a 45-fold fluorescence enhancement at 459 nm in the presence of ClO- and displayed an excellent selectivity over other competing species. The probe featured a fast response time (< 15 s), which could be in favor of the real-time detection towards ClO-. Meanwhile, probe CMM could effectively monitor ClO- in physiological pH condition and the detection limit was estimated to be as low as 5.7 nM. Furthermore, its preeminent recognition properties made the successful application for monitoring ClO- in environmental water samples and labeling CIO- in living biological cells.