An innovative fluorescent probe for monitoring of ONOO- in multiple liver-injury models.

The liver plays a pivotal role in numerous critical physiological processes, functioning as the body's metabolic and detoxification center. Chronic liver disease can precipitate more severe health complications. The onset and progression of liver disease are often characterized by abnormal concentrations of ONOO^-, a highly reactive species whose direct capture and detection in physiological environments pose significant challenges. This work presents an innovative fluorescent probe NAP-ONOO derived from 1,8-naphthalimide, specifically engineered to dynamically monitor fluctuations of ONOO^- levels during liver injury. Due to its high biocompatibility, NAP-ONOO enabled to observe varying degrees of ONOO^- up-regulation across models of liver inflammatory injury, alcohol-induced damage, and drug-induced hepatotoxicity in cellular systems as well as in zebrafish and mice models. These findings highlight the potential of NAP-ONOO for identifying and detecting the liver injury biomarker ONOO^-. Furthermore, NAP-ONOO serves as potent tool for the identification of liver injuries, drug screening, and cellular imaging analyses, thereby promising avenues for future research endeavors.