Phosphorescent iridium(III) complex for efficient sensing of hypochlorite and imaging in living cells

In consideration of the strong oxidizing power of hypochlorite (ClO-), which could cleave C=N moiety, a cyclometalated iridium (III) complex (Ir-Ts) modified hydrazide group as the response unit was synthesized to sensitively and selectively detect ClO- under neutral condition. Upon addition of ClO-, a 21-fold emission enhancement at 574 nm was observed and phosphorescent product was formed due to the cleavage of C=N moiety. The probe Ir-Ts displayed rapid response ( < 15 s) and high selectivity toward ClO- with a low detection limit of 86 nM. More importantly, bioimaging of ClO- was further studied in living cells.