AIE functionality ratiometric fluorescent probe based on quinoline-malononitrile for detection of ONOO^- and its...

Peroxynitrite (ONOO^-), a highly reactive endogenous reactive oxygen species (ROS), plays pivotal roles in diverse physiological and pathological processes, the development of sensitive and reliable strategy for efficiently detecting ONOO^- is helpful to understand its biological functions in biological systems. Here, a novel AIEgen fluorescent probe QM-NP was developed by utilizing quinoline-malononitrile fluorophore as the light-emitting core and aryl borate moiety as the specific ONOO^- recognition group. Upon reaction with ONOO^-, QM-NP exhibits remarkable ratiometric fluorescence response with a distinct emission shift from red (630 nm) to green (540 nm), with higher specificity for ONOO^- compared to other analytes (ROS and RNS), rapid response (<10 s) and high sensitivity (LOD = 1.96 μM). Based on these superior spectral properties and its low toxicity, QM-NP has been successfully employed for ratiometric fluorescence imaging of ONOO^- in living cells and zebrafish, demonstrating its potential as a powerful tool for investigating ONOO^--associated biological mechanisms.