Design, Synthesis and Application of Peroxynitrite Anion Fluorescent Probe with Large Stokes Shift

Peroxynitrite anion (ONOO-), which is originated from the reaction of nitric oxide (NO) and superoxide anion (O-2(-)), plays a pivotal role in immune defense and signal regulation. Excessive levels of ONOO(- )may induce the occurrence of various diseases such as Alzheimer ' s disease, inflammation, cardiovascular disease and cancer, etc. Existing detection methods for ONOO(- )have limitations such as complexity, time consumption, and low cell biocompatibility. In this study, a novel fluorescent probe QFPD was developed using quinoline and diphenylphosphinamide as fluorescent keleton and recognition group, respectively. The strong oxidizing property of ONOO-triggerd the cleavage of phosphoramide bond, leading to fluorescence quenching and a visible color change of the solution from yellow to purple, thereby enabling "ON-OFF" type recognition of ONOO-.QFPD exhibited excellent characteristics including good selectivity and high sensitivity in fluorescence detection (Limit of detection of 1.37 mu mol/L), large Stokes shift (130 nm), rapid response (10 min), and strong anti-interference ability. Additionally, QFPD demonstrated good biocompatibility and could realize real-time dynamic monitoring of endogenous ONOO-.Furthermore, QFPD was successfully applied to environmental toxicology research by visualizing the oxidative stress effects induced by microplastics polymethyl methacrylate (PMMA) and Hg2+ exposure, which might be a novel tool for the mechanism research on oxidative stress associated with microplastic pollution and heavy metal exposure.