多巴胺在十二烷基苯磺酸钠自组装膜电极上的电化学行为和分析应用  

Electrochemical behavior of dopamine at dodecyl benzenesulfonate self-assembled monolayers modified electrode and its application

作　　者：韩晓霞[1] 高作宁[1] 

机构地区：[1]宁夏大学化学化工学院能源化工重点实验室,宁夏银川750021

出　　处：《药学学报》2007年第4期413-417,共5页Acta Pharmaceutica Sinica

基　　金：教育部科学研究重点资助项目(204149);宁夏高等学校科学研究基金资助项目(2006).

摘　　要：制备了十二烷基苯磺酸钠(sodium dodecyl benzenesulfonate,SDBS)自组装膜修饰碳糊电极(SDBS/CPE),并研究了多巴胺(dopamine,DA)在SDBS/CPE上的电化学及电化学动力学性质。用循环伏安法(cyclic voltammetry,CV)、计时电流法(chronoamperometry,CA)和计时库仑法(chronocoulometry,CC)探讨DA在SDBS/CPE上的电化学及电化学动力学性质,用方波伏安法(square wave voltammetry,SWV)考察了氧化峰电流与DA浓度的关系。结果表明,在SDBS/CPE上DA峰电位差减小149 mV,测得DA的电荷转移系数α为0.61,扩散系数D为3.6×10-5cm2.s-1,反应速率常数kf为4.2×10-3cm.s-1。方波伏安法研究表明DA的氧化峰电流与其浓度在2.0×10-6～1.0×10-3mol.L-1呈线性关系,检出限为9.0×10-7mol.L-1,r为0.9979。SDBS/CPE对DA的电化学氧化还原过程产生促进作用,该方法可用于多巴胺注射液中DA含量的测定。Sodium dodecyl benzenesulfonate （SDBS） self-assembled monolayers in situ modified electrode （SDBS/CPE） was prepared. The electrochemical behaviors of dopamine （DA） on SDBS/CPE were studied. Electrochemical behaviors and kinetic parameters of DA were investigated at SDBS/CPE by cyclic voltammetry （CV）, chronoamperometry （CA） and chronocoulometry （CC）. The changes of the oxidation peak currents with concentration of DA were examined by square wave voltametry （SWV）. The difference of peak potential at CPB/CPE was less than 149 mV comparing with that at CPE. The charge transfer coefficient α, diffusion coefficient D and the apparent reaction rate constant kr are 0.61, 3.6 × 10^-5 cm^2 · s^-1 and 4.2 × 10^-3 cm · s^-1, respectively. The oxidation peak currents of DA versus its concentration have a good linear relationship in the concentration range of 2.0 × 10^-6 - 1.0 × 10^-3 mol · L^-1 with the correlation coefficient of 0. 997 9 and the detection limit of 9.0 × 10^-7 mol · L^-1 by square wave voltammetry （SWV） response. The modified electrode showed an excellent electrocatalytic activity for the DA electrochemical oxidation. The method can be applied in the determination of DA in injection samples with the satisfactory results.

关 键 词：多巴胺 十二烷基苯磺酸纳 自组装膜 碳糊电极 电化学 

分 类 号：O657.1[理学—分析化学] R917[理学—化学]