Development of a lysosome-targeted iridium (III) complex-based fluorescent probe for detection of HOCl and its application in living cells and water samples

[Display omitted] •A “turn off” Ir(III) complex-based green fluorescent probe for HOCl was synthesized.•The probe could locate lysosome and detect HOCl in Hela cells.•The probe could quantitatively detect HOCl in real water sample. An iridium(III) complex-based lysosome-targeted green fluorescent probe Ir-PFBS was successfully applied to detect hypochlorous acid in living cells and ambient water samples. The morpholine group in the probe Ir-PFBS not only improved its water solution, but also allowed it to locate lysosome. Photophysical and photochemical property studies demonstrated that probe Ir-PFBS possessed kinds of advantages, such as excellent water solution, high specificity and selectivity for HOCl, and large Stokes shift. For the probe Ir-PFBS in PBS solution (pH = 7.4), strong green fluorescence at 565 nm was observed, which gradually decreased within 30 min after addition of HOCl. Meanwhile, probe Ir-PFBS could be used for hypochlorous acid detection in cells and the actual water sample environment.