A Novel Phenoxazine‐based Fluorescent Probe for the Detection of HOCl in Living Cells.

Hypochlorous acid (HOCl), one of the reactive oxygen species (ROS), is a key microbicidal agent which is used for natural defense. However, it is also linked to varieties of human diseases owing to the overproduction of HOCl. Much effort has been made to exploit selective fluorescent sensors for the detection of HOCl, but most of them have some disadvantages such as short excitation wavelength, low selectivity, and slow response and so on. These restrict the biological application of the probes. In this work, BR‐O was designed and synthesized on the base of phenoxazine for the detection of HOCl. BR‐O exhibited a violent fluorescence enhancement in the presence of HOCl, showing excellent selectivity and high sensitivity. More importantly, the probe BR‐O was capable of detecting exogenous and endogenous HOCl in living cells. [ABSTRACT FROM AUTHOR]