Institute of Chemistry, Jan Kochanowski University of Humanities and Sciences, Swietokrzyska Street 15G, Kielce, Poland.
Bioelectrochemistry. 2010 Aug;79(1):57-65. doi: 10.1016/j.bioelechem.2009.11.002. Epub 2009 Dec 3.
The electrochemical oxidation of 3,4-dihydroxyphenylacetic acid (DOPAC) on a carbon fiber microelectrode (CF) and a glassy carbon macroelectrode (GC) in glacial acetic acid solutions was investigated using voltammetric techniques. Voltammograms recorded at these electrodes show well-defined single waves or peaks. The proposed mechanism of the anodic oxidation of DOPAC consists of two successive one-electron one-proton steps. The loss of the first electron proceeds irreversibly and determines the overall rate of the electrode process. This stage is accompanied by the generation of an unstable phenoxyl radical in position 4 of the aromatic ring. The second stage of the electrode reaction produces substituted orto-quinone as the final product of the electrode process of DOPAC. DOPAC exhibits more antioxidative power than synthetic BHT and can be useful in food protection against reactive oxygen species. The results presented can help to explain biochemical and antioxidative properties of DOPAC in a living cell and can be useful in determination of this compound in real samples.
在冰醋酸溶液中，使用伏安技术研究了 3,4-二羟基苯乙酸（DOPAC）在碳纤维微电极（CF）和玻碳大电极（GC）上的电化学氧化。在这些电极上记录的伏安图显示出清晰的单波或峰。DOPAC 阳极氧化的提议机制由两个连续的单电子单质子步骤组成。第一个电子的损失是不可逆的，决定了电极过程的整体速率。此阶段伴随着不稳定的苯氧自由基在芳环的 4 位生成。电极反应的第二阶段产生取代的邻醌作为 DOPAC 电极过程的最终产物。DOPAC 表现出比合成 BHT 更强的抗氧化能力，可用于保护食物免受活性氧的侵害。所呈现的结果有助于解释 DOPAC 在活细胞中的生化和抗氧化特性，并可用于实际样品中该化合物的测定。
