基于电化学循环伏安法,讨论了3种低成本自制工作电极——银电极、碳糊电极和玻碳电极在茶多酚含量测定应用上的可行性。通过分析茶多酚在电极表面的氧化还原行为,发现所制银电极不适宜检测茶多酚,碳糊电极、玻碳电极的氧化电流峰值与茶多酚含量有良好的线性关系。所制玻碳电极测定绿茶茶样中的茶多酚含量的重复性和准确性较碳糊电极好。与国标方法相比,碳糊电极、玻碳电极检测茶多酚所需时间大大缩短。结果表明,电化学方法可应用于茶多酚含量的快速测定,从而为快速、低价、便捷检测茶多酚提供一条新思路。
The possibility of electrochemistry-cyclic voltammetry (CV) method applied on the fast measurement of green tea polyphenols content was investigated. Three kinds of working electrodes, silver electrode, carbon paste electrode and glassy carbon electrode, were designed and self-made for that purpose. The results showed that the silver electrode was not suitable for the content determination. A linear relationship between the anodic current and the polyphenols concentration was obtained using the carbon paste electrode or the glassy carbon electrode. Test results of green tea samples indicated that the repeatability and accuracy of the glassy carbon electrode were better than the carbon paste electrode. Compared with the national standard method, the electrochemistry method costs much less time. This research confirmed the feasibility of this method and gave a new idea to develop a fast, simple and low-cost way to detect polyphenols in tea.
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