Differentiation of Superoxide Radical Anion and Singlet Oxygen and Their Concurrent Quantifications by Nuclear Magnetic Resonance.
Juhyeon ParkHong TangPeng ZhangPublished in: Analytical chemistry (2023)
While there have been various techniques, assays, and commercial kits developed to measure reactive oxygen species (ROS) with varying degrees of success, there is a lack of innovative methods to differentiate and quantify them simultaneously. In this work, we demonstrate a 19 F nuclear magnetic resonance (NMR)-based method to differentiate two important types of ROS, superoxide radical anion and singlet oxygen, and to quantify them concurrently. By taking advantage of the unique chemical reactivity of two fluorine-containing molecules, 4-fluoro-3-methylphenyl boronic acid and 4-fluoro-3-methylphenol, serving as 19 F NMR probes, we are able to differentiate and quantify, for the first time, superoxide radical anion and singlet oxygen generated by photosensitizers (PSs) concurrently. The results reveal that relative amounts of superoxide radical anion and singlet oxygen generated by a PS under light illumination are oftentimes sensitive to the environment, such as the presence or absence of electron donors. This method provides a means to identify the type of mechanism by which a PS functions under a given condition. We envision that this relatively simple, yet robust, method would be beneficial to a broad range of ROS-pertinent studies, such as photodynamic therapy and photoredox reactions.
Keyphrases
- magnetic resonance
- reactive oxygen species
- photodynamic therapy
- ionic liquid
- hydrogen peroxide
- positron emission tomography
- dna damage
- cell death
- fluorescence imaging
- high resolution
- contrast enhanced
- computed tomography
- high throughput
- genome wide
- squamous cell carcinoma
- gene expression
- pet imaging
- single molecule
- single cell
- locally advanced
- dna methylation