Nano-sized aggregation induced emissive probe for highly sensitive hypochlorous acid detection

A highly sensitive aggregation-induced emissive probe KG1 was developed for detecting hypochlorous acid in an aqueous medium. The KG1 aggregates display excellent fluorescence in a THF:water (10:90) ratio, and the derived aggregates were thoroughly characterized by HRTEM and photophysical investigations. The results indicate that KG1 aggregates have a spherical in shape with an average particle size of 5 nm. Further, the light scattering capability of KG1 aggregates is validated through the Tyndall effect. The KG1 aggregates have a high fluorescence lifetime (∼6 ns) and a quantum yield of 46%, making them suitable for bio-imaging and sensing applications. The sensing ability of KG1 aggregates is evaluated by titrating various concentrations of hypochlorous acid in an aqueous medium. Notably, probe KG1 can detect hypochlorous acid without interference and has a low detection limit of 667 pM. The sensing mechanism was demonstrated through HRMS analysis. Overall, as a result of its excellent fluorescent and sensing properties, the probe KG1 was successfully applied to visualize hypochlorous acid in zebrafish. As a result, this probe is expected to be a prospective tool for investigating the biological mechanisms of hypochlorous acid in living systems.