A highly selective and ultrafast near-infrared fluorescent turn-on and colorimetric probe for hypochlorite in living cells.

Hypochlorous acid (HOCl)/hypochlorite (OCl), important reactive oxygen species, play essential roles in many physiological and pathological progresses. Accordingly, we developed a novel dicyanomethylene-4H-pyran (DCM)-based probe DCM-OCl for colorimetric and near-infrared fluorescent turn-on detection of OCl. The probe exhibited excellent selectivity and sensitivity for OCl over other bio-related analytes with a detection limit of 80 nM. The excellent selectivity of DCM-OCl for OCl was ascribed to specific oxidative cleavage of the dimethylthiocarbamate (DMTC) recognition unit by OCl. Moreover, DCM-OCl exhibited an ultrafast turn-on response (<3 s) to OCl, potentially allowing real-time detection of OCl. Furthermore, DCM-OCl was successfully used to image endogenous/exogenous OCl in living cells.