An aggregation-induced emission (AIE)-active fluorescent chemodosimeter for selective sensing of hypochlorite in water and solid state: Endogenous detection of hypochlorite in live cells

Hypochlorite (ClO−) being an important reactive oxygen species plays a crucial role in the oxidative damage to tissue and other various diseases. Highly selective, sensitive, and quick detection of aberrant ClO− is vital for the protection of living organisms and the environment. Accordingly, fluorescent molecules are most effective sensor system for ClO−. Herein, we have synthesized and characterized a water soluble AIE-active tetraphenylethylene (TPE)-based fluorescent molecule TPE−Py+ (TPP) for rapid (10 s) and selective detection of ClO− based on ClO− induced oxidation of N-alkylpyridinium to N-methyl-2-pyridone. ClO− mediated aggregation-induced emission (AIE) enhancement corresponds to turn-on response. Scanning electron microscopic (SEM) study supports AIE behavior of the probe upon treatment with ClO−. The detection limit of TPP for ClO− was found to be 8.89 nM and exhibited high selectivity among other possibly interfering analytes (ROS, RNS, other ions). TPP-based handy test kits were developed for the solid-state detection of ClO− in environmental samples. Furthermore, our probe was effective in detecting ClO− in real water samples, fetal bovine serum and able to detect endogenous ClO− in live cell.