Insights Into the Detection Selectivity of Redox and Non-redox Based Probes for the Superoxide Anion Using Coumarin and Chromone as the Fluorophores

Front Chem. 2021 Nov 25:9:753621. doi: 10.3389/fchem.2021.753621. eCollection 2021.

Abstract

In this study, we evaluated the applicability of various superoxide anion sensors which were designed based on either redox or non-redox mechanisms. Firstly, both redox- and non-redox-based superoxide anion probes were designed and synthesized using either coumarin or chromone as the fluorophores, and the photophysical properties of these probes were measured. Subsequently, the sensing preference of both types of probes toward various reactive oxygen species (ROS) was evaluated. We found that non-redox-based O2 •- probes exhibited broad sensing ability toward various ROS. By contrast, redox based O2 •- probes showed a clear reactivity hierarchy which was well correlated to the oxidizing strength of the ROS. Lastly, the detection selectivity of redox-based O2 •- recognizing probes was also observed when balancing various factors, such as reactant ROS concentrations, temperature, and changing reaction transformation rates. Herein, we concluded the selectivity advantage of redox-based O2 •- probes.

Keywords: ROS; coumarin; non–redox-based probes; redox-based probes; selectivity; superoxide anion.