四环素在碳纳米管修饰电极上的电化学行为研究

Electrochemical Behavior of Tetracycline on the SDBS-MWCNT Modified Electrode

研究了四环素(TC)在多壁碳纳米管(MWCNT)/十二烷基苯磺酸钠(SDBS)复合膜修饰玻碳电极上的电化学行,为并探讨了其电极过程机理.实验结果表明,在pH=3的柠檬酸-柠檬酸钠缓冲溶液中,此修饰电极对四环素表现出强的电催化效应;其电极反应为扩散控制的不可逆电极过程,两电子三质子参加电化学反应,电极反应的电子转移系数为0.53.峰电位为-1.056 V,峰电流与TC浓度在4.49×10-7～1.46×10-5mol/L范围内呈良好线性关系,检出限为3.59×10-7mol/L.该方法测定鱼塘水样中TC残留量,结果令人满意.修饰电极表现出很好的稳定性和选择性.

In this paper we used sodium dodecyl benzene sulfonate(SDBS) and MWCNT to modify glassy carbon electode,which was characterized by cyclic voltammetry and systematically studied the electrochemical behavior of TC on the SDBS-MWCNT modified electrode.According to the experiment,the modified electrode showed high electrocatalytic effect on TC in C6H8O7-C6H5Na3O7 media;the electrode reaction was controlled by the diffusion process and irreversible electrode processes,the reaction of TC on the modified electrode involved two electrons and three protons,the charge-transfer coefficient is 0.53,which is consistent with the theoretical calculations.Under optimal conditions,the peak currents(-1.056 V) increased with the increasing TC concentrations in the range of 4.49×10-7~1.46×10-5 mol/L with a linear coefficiency of 0.997.Besides,the limit of detection was 3.59×10-7 mol/L.This method was successfully applied to the determination of the TC residues in environment,and the modified electode showed good stability and selectivity.