L-半胱氨酸自组装金电极测定鲜橙多中抗坏血酸的含量  

Determination of ascorbic acid of the beverage by the self-assembled film modified electrode

作　　者：王亚珍[1] 郑武[2] 

机构地区：[1]江汉大学化学与环境工程学院,湖北武汉430056 [2]武汉大学医学院附属卫生学校,湖北武汉430060

出　　处：《化学传感器》2008年第3期53-57,共5页Chemical Sensors

基　　金：武汉市晨光计划(No.200750731285)项目资助

摘　　要：该文用循环伏安法研究了抗坏血酸在以L-半胱氨酸作为修饰剂的自组装金电极表面上的电化学行为,并对实验条件进行了优化。实验结果表明,在pH=4.43的HAc-NaAc缓冲溶液中,在-0.2～0.8V扫描电位范围内,相对裸金电极,抗坏血酸在自组装金电极表面出现一对稳定的氧化还原峰。且该氧化峰的峰电流与抗坏血酸的浓度在1.09×10-6～2.13×10-3mol/L呈良好的线性关系,检测限为1.0×10-7mol/L。此外,该自组装膜电极还具有一定的抗干扰能力和较好的稳定性与重现性,用该自组装膜金电极对实际样品鲜橙多中抗坏血酸的含量进行测定,结果令人满意。In this study, electrocatalvtic effect of ascorbic acid on L - cysteine self- assembled film modified gold electrode was studied by cyclic voltammetry. The experimental conditions were optimized. The results indicated that ascorbic acid exhibited very strong electrochemical activity on the self-assembled gold electrode. A pair of stable redox peaks were observed when potential was scanned in HAc -NaAc buffer solution（pH = 4.43） in the potential range of - 0.2 - 0.8 V. The oxidation peak current was linearly related to ascorbic acid concentrations in the range of 1.09×10^-6- 2. 13×10^-3 mol/L and the detection limit is 1.0×10^-7 mol/L. Some interference was tested and 2 - fold uric acid could not interfere the determination of 1.0×10^-4 mol/L ascorbic acid. In this system, the self- assembled Au electrode indicated good stability and reproducibility. It was applied to the determination of ascorbic acid levels in practical samples. The result is satisfactory.

关 键 词：抗坏血酸 自组装膜电极 L-半胱氨酸 循环伏安法 

分 类 号：TS275[轻工技术与工程—农产品加工及贮藏工程]