聚3，4-乙撑二氧噻吩/金复合电极的制备及其在多巴胺检测中的应用

摘要

在水溶液中，以对甲苯磺酸钠为支持电解质，在氧化铟锡导电玻璃上，采用电化学恒电位极化法制备聚3，4-乙撑二氧噻吩（ PEDOT）修饰电极。通过电化学循环伏安法，在PEDOT电极上沉积金纳米颗粒（ Au NPs），制得PEDOT/Au复合修饰电极，用于多巴胺（ DA）的电化学检测。考察了PEDOT/Au复合修饰电极中Au NPs的沉积量对DA电化学检测响应的影响，同时研究了在干扰物质抗坏血酸（ AA）和尿酸（ UA）存在时，PEDOT/Au复合修饰电极对DA的检测。结果表明，在中性pH溶液中，利用PEDOT/Au复合修饰电极，采用差分脉冲伏安法检测DA的线性范围为5×10-6~1×10-4 moI/L，最低检测限可达1×10-8 moI/L，且能有效排除AA和UA的干扰，实现三者的同时检测。%The poIy(3,4-ethyIenedioxythiophene)(PEDOT)eIectrode was synthesized on indium tin ox-ide( ITO)gIass substrate via eIectrochemicaI poIarization under a constant bias in sodium P-toIuenesuI-fonate( TsONa)aqueous soIution. PEDOT/Au composite eIectrode was fabricated through cycIic voItam-metry method and then was used for eIectrochemicaI detection of dopamine( DA). The infIuence of the Ioading amount of Au NPs in the PEDOT/Au composite eIectrode on DA detection was discussed. Further-more,the eIectrochemicaI detection of DA was aIso studied using the PEDOT/Au eIectrode in the pres-ence of ascorbic acid( AA)and uric acid( UA). The resuIt showed that in neutraI aqueous soIution,the DA concentration couId be determined in a Iinear range of 5 × 10 -6 ~1 × 10 -4 moI/L,and the detection Iimit of DA was found to be 1 × 10 -8 moI/L. The resuIts indicated that the PEDOT/Au composite fiIm showed high sensitivity and seIectivity for DA eIectrochemicaI detection even in the presence of interfer-ents Iike AA and UA.