Ratiometric fluorescent detection of hypochlorite in aqueous solution and living cells using an ionic probe with aggregation-induced emission feature

Fluorescent sensors have attracted great research attention for detection of various target substrates in environment and living organisms. However, there are still of some issues when using traditional organic probes owing to their poor water dispersibility and aggregation caused quenching effect. In this paper, we designed and synthesized an ionic fluorescent probe (named as TPY) with aggregation-induced emission (AIE) feature and explored its potential sensor performance towards hypochlorite in aqueous solution and living organisms. The results demonstrated that TPY can detect hypochlorite with excellent selectivity, outstanding sensitivity and fast response time. The reaction mechanism should be ascribed to the reaction between hypochlorite and TPY, that was evidenced by a number of characterization techniques, such as UV–vis/fluorescence spectroscopy, 1H NMR and mass spectroscopy. Most importantly, owing to its amphiphilicity and AIE feature, the probe could be well dispersed in aqueous solution and showed enhanced fluorescence, which endow it good sensor performance in both aqueous solution and living organisms. Finally, the biological assays confirmed that TPY has low toxicity and good biocompatibility, which could be used to detect hypochlorite in living cells. We trust this work will provide some new ideas for designing fluorescent probes with better performance for chemo/biosensors.