Observation of endogenous HClO in living mice with inflammation, tissue injury and bacterial infection by a near-infrared fluorescent probe

HClO is an important signaling species, which is closely related to many diseases and physiological activities of the organism, and it plays an important role in the immune system. Therefore, it is of great significance to accurately and quickly monitor the HClO in the living organisms. However, in vivo detection of endogenous HClO remains a challenge. Herein, a near-infrared fluorescent probe CyClOP for the rapid detection of HClO was developed. CyClOP possesses several advantages such as fast response, good selectivity and deep penetration. CyClOP was successfully applied to the detection of endogenous HClO in living cells. In addition, CyClOP effectively captured the fluctuation of endogenous HClO produced by the immune system during infection with Staphylococcus aureus and muscle tissue injury in living mice for the first time. This work provides a reliable tool for monitoring of endogenous HClO in vivo and in vitro, and it has great potential for future research in HClO-related biology and pathology.