A highly sensitive turn-on fluorescent probe for real-time detecting hypochlorite and its application in living cells

Abstract It is very necessary to develop real-time, highly sensitive and selective fluorescent probes for hypochlorite (ClO−) in living cells owing to hypochlorite's important role in pathological and physiological processes and its short life. Herein, a pyrene Schiff's base derivative was successfully developed for real-time (within seconds), highly sensitive detecting ClO− with a low detection limit (5.7 nM) and wide pH range (4.0–11.0) based on nucleophilic addition and subsequent hydrolysis mechanism. The probe has aggregation-induced emission properties and emits yellow fluorescence (544 nm) in PBS solution, while it exhibits blue fluorescence in other organic solvents (426 nm (THF) - 460 nm (MeOH)). The probe can be used to response ClO− in A549 cells with low cytotoxicity, a good cell membranes penetration and good biocompatibility. Cell uptake experiment indicates that probe getting into the cells is energy-dependent and is not attributed to endocytosis. Moreover, the probe is successfully used in real water sample to detect ClO− and it can be expected to be applied to ClO− participated biological and pathological functions in biological systems.