A ratiometric fluorescent probe for sensitively tracking peroxynitrite during drug‐induced hepatotoxicity

As one of the essential components of reactive oxygen species (ROS), peroxynitrite (ONOO‐) plays an indispensable role in redox homeostasis and signal transduction processes, and its deviant levels are associated with numerous clinical diseases. Therefore, accurate and rapid detection of intracellular ONOO‐ levels is crucial for revealing its role in physiological and pathological processes. Herein, we constructed a ratiometric fluorescent probe to detect ONOO‐ levels in biological systems. The probe represents fast reaction rate (within 15 min), outstanding selectivity, good sensitivity (LOD = 13.32 nM) and stability to ONOO‐, and it was successfully used for visualizing endogenous ONOO‐ in living cells. More importantly, it has also been used for tracking the changes of intracellular ONOO‐ during drug‐induced hepatotoxicity with ratiometric fluorescence.