A near-infrared fluorescent probe for ratiometric imaging peroxynitrite in Parkinson's disease model

As a regular neurodegenerative disease, Parkinson's disease (PD) brings great pain and heavy economic burden to patients. Peroxynitrite (ONOO - ) have attracted great attention to be a neurotoxicity specie in the pathogenesis of PD. Therefore, understanding the physiological functions of ONOO - in PD disease is of great importance to the early diagnoses. Unfortunately, it still lacks effective method for detecting ONOO - in PD model. In this work, a highly sensitivity and selectivity near-infrared ratiometric fluorescent probe (named K-ONOO ) was designed for tracking ONOO - in PD model. K-ONOO exhibited a unique ratiometric response toward ONOO - due to the fracture of the boronic acid ester group and the principle of ICT resulted in red-shifted spectra. K-ONOO exhibited a quantitative response to ONOO - (0–15 μM) with a low detection limit (212 nM). K-ONOO can successfully map the changes of endogenous ONOO - in vivo. The results demonstrated that an elevated degree of ONOO - is closely correlated with zebrafish under rotenone stimulation. More importantly, H 2 S may serve as a neuroprotectant, which helps regulate ONOO - overexpression and prevent oxidative stress-induced neurodegeneration. The visualization imaging of ONOO - based on K-ONOO provides an auspicious method for understanding the essential role of ONOO - during PD disease pathology and early diagnosis. • A NIR fluorescent probe K-ONOO with ratiometric characteristic for imaging ONOO - in PD model was reported. • K-ONOO is the first NIR ratiometric fluorescent probe for imaging ONOO - in PD model. • K-ONOO displayed high specificity toward ONOO - over other reactive oxygen species with a fast response. • K-ONOO was successfully applied for monitoring the fluctuation of ONOO - in PD model. • H 2 S may serve as a latent neuroprotectant to prevent neurotoxin-induced neurodegeneration.