白藜芦醇在银电极上的吸附伏安行为及其应用

白藜芦醇(3,5,4-三羟基芪)通常存在于葡萄、桑椹等多种植物中, 葡萄酒中也有一定的含量1]. 由于白藜芦醇对防治癌症、动脉硬化和冠心病等疾病有较好的疗效1,2], 近年来对白藜芦醇生物活性的研究日益受到重视. 白藜芦醇的测定一般采用高效液相色谱和毛细管电泳等方法3～5], 这些方法均需对样品进行减压浓缩和萃取等处理, 比较繁琐. 本文对白藜芦醇在银电极上的吸附伏安行为进行了研究, 并将其应用于葡萄酒中白藜芦醇含量的直接测定, 获得了较好的实验结果.

Adsorptive Voltammetric Behavior of Resveratrol and Its Application at Silver Electrode

Adsorptive voltammetric behavior of resveratrol at a silver electrode was investigated. And based on this, a linear scan voltammetry for determination of resveratrol had been found. The adsorption corresponded to the Langmuir type isotherm curve, and the free energy of adsorption was caculated to be -46.21 kJ/mol at 298 K. The electrochemical parameters such as charge transfer coefficient α and standard electron transfer rate constant ks were estimated. In 0.2 mol/L KNO3+1.2×10 -4 mol/L KCl solution, resveratrol can give a sensitive anode peak at potential about 0.29 V(vs. SCE). The linear range between the peak current and the concentration of resveratrol is 2.0×10-9 to 1.0×10-8 mol/L and 1.0×10-8 to 9.0×10-8 mol/L, respectively. The detection limit is 4.0×10 -10 mol/L. The method had been applied to the determination of resveratrol in wine.