Photoreduction of the fluorescent dye 2′-7′-dichlorofluorescein:: A spin trapping and direct electron spin resonance study with implications for oxidative stress measurements
Photoreduction of the fluorescent dye 2′-7′-dichlorofluorescein:: A spin trapping and direct electron spin resonance study with implications for oxidative stress measurements
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DOI：
10.1016/s0891-5849(98)00174-9
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发表时间：
1999-01-01
影响因子：
7.4
通讯作者：
Mason, RP
中科院分区：
文献类型：
--
作者：
Marchesi, E;Rota, C;Mason, RP
用直接电子自旋共振（ESR）和ESR自旋捕获技术研究了2 ′-7 ′-二氯荧光素（DCF）在缓冲溶液中的光还原反应。在还原剂存在下对DCF反应的厌氧研究表明，在可见光照射（λ> 300 nm）期间，2 '-7'-二氯荧光素经历单电子还原，产生半醌型自由基，如直接ESR所示。含有DCF、5，5-二甲基-1-吡咯啉N-氧化物（DMPO）和还原型谷胱甘肽（GSH）或还原型NADH的孵育物的自旋捕获研究表明，在可见光照射下，产生超氧化物歧化酶敏感的DMPO/-OOH加合物。在DMPO的情况下，用克拉克型氧电极的测量表明，分子氧消耗在一个光依赖性的过程。DCF的半醌自由基，当在有氧系统中形成时，立即被氧氧化，其再生染料并形成超氧化物。(C)1998年爱思唯尔科学公司
The photoreduction of 2'-7'-dichlorofluorescein (DCF) was investigated in buffer solution using direct electron spin resonance (ESR) and the ESR spin-trapping technique. Anaerobic studies of the reaction of DCF in the presence of reducing agents demonstrated that during visible irradiation (lambda > 300 nm) 2'-7'-dichlorofluorescein undergoes one-electron reduction to produce a semiquinone-type free radical as demonstrated by direct ESR. Spin-trapping studies of incubations containing DCF, 5,5-dimethyl-1-pyrroline N-oxide (DMPO) and either reduced glutathione (GSH) or reduced NADH demonstrate, under irradiation with visible light, the production of the superoxide dismutase-sensitive DMPO/-OOH adduct. In the absence of DMPO, measurements with a Clark-type oxygen electrode show that molecular oxygen is consumed in a light-dependent process. The semiquinone radical of DCF, when formed in an aerobic system, is immediately oxidized by oxygen, which regenerates the dye and forms superoxide. (C) 1998 Elsevier Science Inc.