Michalkiewicz Slawomir
Institute of Chemistry, Swietokrzyska Academy of Kielce, ul. Checinska 5, PL-25020 Kielce, Poland.
Bioelectrochemistry. 2007 May;70(2):495-500. doi: 10.1016/j.bioelechem.2006.08.003. Epub 2006 Sep 1.
The electrochemical reduction of coenzyme CoQ(10) and CoQ(0) on glassy carbon (GC) has been investigated in mixed solvent containing 80 vol.% acetic acid and 20 vol.% acetonitrile. A combination of cyclic voltammetry (CV) and rotating disk electrode technique (RDE) was employed to elucidate the mechanism of electrode processes. The results obtained were interpreted in terms of an E(r)E(q) mechanism involving the inverted ordering of formal potentials, i.e. E(2)(0')>E(1)(0'). The cathodic processes of both compounds consist of two successive one-electron one-proton steps, whereas the second electron transfer is thermodynamically more facile than the first. The processes occur with the generation of unstable semiquinone radicals as primary products. The results presented can help in explanation of the biochemical properties of CoQ(10) in the living cell.
在含有80体积%乙酸和20体积%乙腈的混合溶剂中，研究了辅酶CoQ(10)和CoQ(0)在玻碳(GC)上的电化学还原。采用循环伏安法(CV)和旋转圆盘电极技术(RDE)相结合的方法来阐明电极过程的机理。所得结果根据涉及形式电位反转顺序（即E(2)(0')>E(1)(0')）的E(r)E(q)机理进行解释。两种化合物的阴极过程均由两个连续的单电子单质子步骤组成，而第二次电子转移在热力学上比第一次更容易。这些过程伴随着不稳定的半醌自由基作为主要产物的生成。所呈现的结果有助于解释CoQ(10)在活细胞中的生化特性。
