黄芩甙在玻碳电极上的电化学行为及其应用  

Electrochemical behaviors and determination of baicalin at a glassy carbon electrode

作　　者：延绥宏[1] 郑建斌[1] 汤宏胜[1] 刘波[1] 

机构地区：[1]西北大学分析科学研究所,西安710069

出　　处：《分析试验室》2004年第11期22-25,共4页Chinese Journal of Analysis Laboratory

基　　金：国家自然科学基金项目(20275030);教育部科学技术研究重点项目(02187);高等学校骨干教师资助计划项目(GG 150 71006 2877);陕西省教育厅专项科研基金资助项目(01JK076)

摘　　要：用线性扫描伏安法(LSV)、循环伏安法(CV)和常规脉冲伏安法(NPV)等多种电化学方法研究了黄芩甙在玻碳电极上的电化学行为,并建立了尿样和血清样品中黄芩甙的微分脉冲伏安(DPV)测定法。实验结果表明:黄芩甙在玻碳电极上的吸附符合Frumkin吸附等温式,吸附自由能为-35.01kJ mol。采用整体电解法求得电极反应电子数为2,并结合Nernst方程式推导了反应机理。黄芩甙在玻碳电极上预富集后,在4.20×10-10～1.05×10-5mol L范围内分段呈线性关系,对5.60×10-7mol L黄芩甙溶液连续6次测定的RSD=2.0%,检出限为2.8×10-10mol L。Electrochemical behaviors of Baicalin have been examined by means of linear-sweep voltammetry, cyclic voltammetry and normal pulse voltammetry, and a differential pulse voltammetry for determination of Baicalin in urine and serum samples has been established. The (adsorption) behavior of Baicalin at the glassy carbon electrode was investigated. The adsorption corresponded to a Frumkin type isotherm and the free energy of adsorption was calculated to be -35.01 kJ/mol at 22 ℃. Bulk electrolytic method was used to measure the number of electrons transferred in the oxidation reaction, and the mechanism of the electrode reaction was suggested. The detection limit is 2.80×10^(-10) mol/L, and the relative standard deviation(RSD) is 2.02% for 5.60×10^(-7) mol/L Baicalin (n=6).

关 键 词：伏安法 玻碳电极 吸附 黄芩甙 

分 类 号：O657.1[理学—分析化学]