Demonstrating HOCl as a potential biomarker for liver fibrosis using a highly sensitive fluorescent probe

The spatiotemporal inspection of ROS behavior during liver fibrosis (LF) progression can facilitate its diagnosis and anti-oxidant therapy. However, none of fluorescent probes for ROS has been devoted to this issue. In this study, we proposed a HOCl-specific fluorescent probe to monitor LF process for the first time. The probe was featured with easy preparation, high selectivity, superb sensitivity (0.97 nM), rapid response (within seconds), and good membrane permeability. It can monitor delicate cellular HOCl changes from various endo-sources, and discriminate different cell types (normal or cancer) according to their inherent HOCl levels. Especially, we constructed two LF rat models by either chemical treatment (CCl4 injection) or surgical operation (bile duct ligation), and for the first time observed that HOCl level in LF tissues increased along with its stage of development while that during acute liver injury or liver cirrhosis was unchanged or reduced. The results strongly evident the potential of HOCl as a unique biomarker for LF detection and even clinical diagnosis.