Construction of a NIR fluorescent probe for tracking mitochondrial HOCl during liver injury

The inappropriate or excessive drug and alcohol consumption is a major cause of liver injuries. The development of a tool capable of visualizing the liver injury process with high precision, and in real time is particularly urgent. In this study, we designed and synthesized a novel HOCl-responsive fluorescent probe, PTZ-NS, for tracking mitochondrial HOCl during liver injury. PTZ-NS exhibits excellent sensitivity and selectivity for HOCl, with a detection limit of 158 nM. It can specifically target mitochondria, and successfully distinguishing between HepG2 and L-02 cells. The probe was also effective in tracking changes of endogenous HOCl levels in cells and zebrafish, and it was used to capture the increase in HOCl content during ferroptosis. Crucially, PTZ-NS was successfully employed to monitor HOCl during alcohol-induced liver disease (AID) and drug-induced liver injury (DILI) in mice liver tissue. Overall, PTZ-NS not only facilitate the real-time and precise observation of liver injury but also open up promising avenues for future disease prevention and research.