Visualization of the endogenous ONOO- in the drug-induced liver injury mice by a mitochondria-targeting ratiometric fluorescence probe.

Fluorescence spectroscopy has attracted considerable interest owing to its distinct advantages. In Particular, ratiometric fluorescence probes enable more accurate quantitative detection in complex biological specimens. As a key member of the reactive nitrogen species (RNS) family, peroxynitrite (ONOO-) plays critical roles in physiological and pathological processes. Drug-induced liver injury (DILI), a global health concern, represents a major contributor to advanced liver diseases, including hepatocellular carcinoma. Although ONOO- serves as an important biomarker of hepatotoxicity, the visualization of endogenous ONOO- in DILI models remains challenging, primarily due to the scarcity of specific ratiometric probes. Herein, we report a novel mitochondria-targeting ratiometric fluorescent probe, Mito-P, based on a xanthene scaffold. Mito-P shows high sensitivity, excellent selectivity, and robust anti-interference capability toward ONOO-. Using probe Mito-P, we demonstrate real-time fluorescence imaging of intracellular ONOO-. Besides, Mito-P enables the monitoring of ONOO- dynamics in DILI models. We anticipate that Mito-P will serve as a powerful molecular tool for elucidating the pathophysiological roles of ONOO-.