Fluorescent Probes for HOCl Imaging

Abstract Small‐molecule fluorescent probes for hypochlorous acid (HOCl), one of the poorly understood reactive oxygen species (ROS), help to unveil HOCl functions in health and disease. Numerous small‐molecule HOCl fluorescent probes have been developed in the past decade. Nevertheless, only a portion of them demonstrated their practical applications in biomedical research because of common problems in selectivity, sensitivity, chemostability, and photostability, etc. The problems could be addressed by a combination of rational probe design and careful selection of fluorophore templates. In this review, we describe several classes of representative HOCl fluorescent probes based on their fluorophore templates, and we discuss their design strategies, photophysical properties, and biological applications. A comprehension of their strengths, weaknesses, and common uses will facilitate the development of ideal HOCl assays and the discovery of novel biological processes.