A novel target and pH dual-activatable fluorescent probe for precisely detecting hypochlorite in lysosomes.

Hypochlorite (HClO) is involved in various physiological and pathological processes as well as regulation of lysosomal functions. Thus, it is appreciated to develop efficient molecule tools for precisely detecting HClO in lysosomes. Although several lysosomal-targetable fluorogenic probes for HClO have been developed to date, they still suffered from the discounted sensing performance under lysosomal acidic condition. Herein, on the basis of the "AND" logic gate strategy, a novel dual-activatable fluorogenic probe CS has been rationally designed by simultaneously incorporating HClO recognition site and pH-sensitive group with lysosomal-targetable characteristic into a coumarin fluorophore. Different from the single-activated ones previously reported, CS exhibited good sensitivity, high specificity and fast response towards HClO under the acidic conditions but was out of operation in the neutral or alkaline environment. Importantly, it had been successfully applied for spatial-resolution imaging of exogenous or endogenous HClO in lysosomes. A novel dual-activatable fluorogenic probe CS has been rationally designed. This probe exhibited good sensitivity, high specificity and fast response towards HClO under the lysosomal acidic conditions, and it has been successfully applied for visualizing exogenous or endogenous HClO in lysosomes of living cells. Image 1 • A novel dual-activatable fluorescent probe CS for HClO and acidic condition was rationally designed. • The probe exhibited good sensitivity, high specificity and fast response towards hypochlorous acid. • The probe was applied to detect exogenous and endogenous hypochlorous acid in living cells. • The probe demonstrated an excellent lysosome-targetable ability. [ABSTRACT FROM AUTHOR]