期刊
FREE RADICAL BIOLOGY AND MEDICINE
卷 49, 期 2, 页码 275-281出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.freeradbiomed.2010.04.010
关键词
Uric acid; Peroxynitrite; ESR; Electron spin resonance; Mass spectrometry; LC-MS; Free radicals; Spin trap; PBN
资金
- National Science Foundation [CHE-0809725]
- NIH [HL-68607]
- Gatorade
Peroxynitrite is a reactive oxidant produced in vivo in response to oxidative and other stress by the diffusion-limited reaction of nitric oxide and superoxide. This article is focused on the identification of free radical intermediates of uric acid formed during its reaction with peroxynitrite. The experimental approach included the ESR spin trapping of the radical generated from the reaction between uric acid and peroxynitrite at pH 7.4 and mass spectrometry studies of the trapped radicals. Using PBN (N-tert-butyl-alpha-phenylnitrone) as the spin trapping agent, a six-line ESR spectrum was obtained and its hyperfine coupling constants, a(N) = 15.6 G and a(H) = 4.4 G. revealed the presence of carbon-based radicals. Further structural identification of the PBN-radical adducts was carried out using liquid chromatography-mass spectrometry. After comparison with the control reactions, two species were identified that correspond to the protonated molecules (M + 1) at m/z 352 and 223, respectively. The ions of m/z 352 were characterized as the PBN-triuretcarbonyl radical adduct and the m/z 223 ion was identified as the PBN-aminocarbonyl radical adduct. Their mechanism of formation is discussed. (C) 2010 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据