Li Dan, Deng Wei, Xu Hu, Sun Yinxing, Wang Yuhong, Chen Shouhui, Ding Xianting
School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai, P. R. China.
School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai, P. R. China
J Lab Autom. 2016 Aug;21(4):579-89. doi: 10.1177/2211068216644442. Epub 2016 Apr 19.
The electrochemistry reduction of coenzyme Q10 (CoQ10) on silver electrodes has been investigated in mixed solvent containing 95 vol. % ethanol and 5 vol. % water. A combination of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) is employed to explore the mechanism of redox processes of CoQ10 in the presence and absence of oxygen, respectively. It has been proved that the redox reaction of CoQ10 is highly dependent on the oxygen in the solution compared with that of CoQ0, which may be attributed to the isoprenoid side chain effect of CoQ10 Moreover, the effects of experimental variables such as electrolyte component, pH, temperature, and sonication time on the amperometric and potentiometric responses of CoQ10 are presented. The differential pulse voltammetry method has been developed for the quantification of the CoQ10 in the complex samples. Under the optimum conditions, the method is linear over the concentration range of 1.00 × 10(-7) to 1.00 × 10(-3) mol/L (8.63 × 10(-2) to 8.63 × 10(2) mg/kg). The limit of detection (3σ/k) is 3.33 × 10(-8) mol/L (2.88 × 10(-2) mg/kg). The recoveries of the spiked samples are between 91% and 108%. The presented method can be applied to the analysis of CoQ10 in real samples without any pretreatment.
在含有95体积%乙醇和5体积%水的混合溶剂中，研究了辅酶Q10（CoQ10）在银电极上的电化学还原。分别采用循环伏安法（CV）和电化学阻抗谱（EIS）来探究CoQ10在有氧和无氧条件下的氧化还原过程机理。结果表明，与CoQ0相比，CoQ10的氧化还原反应对溶液中的氧高度依赖，这可能归因于CoQ10的异戊二烯侧链效应。此外，还介绍了电解质成分、pH值、温度和超声处理时间等实验变量对CoQ10安培和电位响应的影响。已开发出差分脉冲伏安法用于复杂样品中CoQ10的定量分析。在最佳条件下，该方法在1.00×10⁻⁷至1.00×10⁻³mol/L（8.63×10⁻²至8.63×10²mg/kg）的浓度范围内呈线性关系。检测限（3σ/k）为3.33×10⁻⁸mol/L（2.88×10⁻²mg/kg）。加标样品的回收率在91%至108%之间。所提出的方法可应用于实际样品中CoQ10的分析，无需任何预处理。
