邻苯二胺在L-酪氨酸功能化的玻碳电极上的聚合及其性能  

Polymerization of o-Phenylenediamine on L-Tyrosine Functionalized Glassy Carbon Electrode and Its Electrochemical Activity

作　　者：廉继英[1] 张雷[1] 

机构地区：[1]上海师范大学生命与环境科学学院化学系,上海200234

出　　处：《理化检验（化学分册）》2009年第6期624-628,共5页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：上海市教育委员会资助项目(05DZ16);上海师范大学(PL507)资助项目

摘　　要：首先在非水介质中通过电化学氧化将L-酪氨酸以C—N键共价键合在玻碳电极表面，形成L-酪氨酸接枝单层膜。再在L-酪氨酸功能化的玻碳电极上对邻苯二胺进行电化学聚合，从而制备了聚邻苯二胺／L-酪氨酸复合膜修饰玻碳电极（聚-o—PD-Tyr／GCE）。研究发现聚-o—PD-Tyr／GCE在pH6．8的磷酸缓冲溶液（PBS）中对抗坏血酸的电化学氧化具有催化作用，其氧化电位为0．35V，比在裸玻碳电极上（0．58V）降低了0．23V，峰电流也明显升高。抗坏血酸在修饰电极上响应电流与其浓度在2．5×10^-4～1．5×10^-3mol·L^-1范围内呈线性关系，检出限（3s／k）为43．64μmol·L^-1。经修饰的电极保存在0．1μmol·L^-1 PBS中，可至少稳定5d。对5×10^-4mol·L^-1抗坏血酸溶液连续测定10次，测得此电极的相对标准偏差为3．2％。Glassy carbon electrode （GCE） modified with composite membrane of poly-o-phenylene diamine and L-tyrosine （poly-o-PD-Tyr/GCE） was prepared by electropolymerization of o-phenylene diamine onto the L-tyrosine functionalized GCE which was obtained by covalent bonding of L-tyrosine to the surface of GCE through C--N bond via electro-oxidation. It was found that in a PBS of pH 6. 8, the modified electrode, poly-o-PD-Tyr/ GCE, behaved to catalyze the electro-oxidation of ascorbic acid at the oxidation potential of 0. 35 V, which is 0. 23 V lower than that at the bare GCE. Linear relationship between values of oxidation peak current （Ip） and concentration of ascorbic acid was obtained in the range of 2. 5×10^-4 -- 1.5×10^-3mol·L^-1. Detection limit （3s/k） of the electrode toward ascorbic acid was found to be 43. 64μmol·L^-1. No significant change of current response was observed within 5d when the electrode was kept in 0. 1 mol·L^-1 PBS （pH 6. 8）. Value of RSD （n=10） of 3. 2% was found when precision of measurements with the electrode was tested with ascorbic acid solution of 5 ×10^-4mol·L^-1.

关 键 词：聚邻苯二胺/L-酪氨酸复合膜 抗坏血酸 电催化作用 

分 类 号：O657.1[理学—分析化学]