基于聚溴酚蓝-石墨烯复合膜修饰电极的多巴胺电化学传感器  

Electrochemical Sensing of Dopamine Based on Poly(bromophenol blue)-Graphene Composite Modified Electrode

作　　者：陈苏靖 李芳芳[1] 钟云秀 吴白云[1] 胡岱玉 郑伟[1] 郑冬云[1,2,3] 

机构地区：[1]中南民族大学生物医学工程学院,湖北武汉430074 [2]中南民族大学脑认知国家民委重点实验室,湖北武汉430074 [3]中南民族大学医学信息处理与肿瘤早期诊疗湖北省重点实验室,湖北武汉430074

出　　处：《分析测试学报》2015年第9期1066-1071,共6页Journal of Instrumental Analysis

基　　金：国家自然科学基金(61178087;61501526);中南民族大学中央高校基本科研业务费专项资金项目(CZY14017;CTZ12001);中南民族大学科研团队项目(XTZ09002);中南民族大学大学生创新创业训练计划项目(KYCX140605Z)

摘　　要：借助于简单可控的滴涂成膜和在线电聚合方法,将溴酚蓝和石墨烯修饰到玻碳电极表面,制备出聚溴酚蓝（PBPB）-石墨烯（GO）复合膜修饰玻碳电极（GCE）,即多巴胺（DA）电化学传感器。研究表明,PBPB-GO复合膜对DA的电化学还原具有良好的催化作用。电化学交流阻抗表征结果显示,相对于裸GCE和PBPB/GCE,PBPB/GO/GCE具有较低的表面电阻,有利于加快电子传递;扫描电镜表征结果显示,PBPB/GO/GCE具有疏松多孔的结构,有利于对DA的富集。对DA在PBPB/GO/GCE上的电化学传感机理进行考察,结果显示其电化学反应是一个受吸附控制且有质子参与的过程。对DA的检测条件进行优化,溴酚蓝的最佳聚合圈数为15,石墨烯（2 mg/m L）的最佳修饰量为2μL,最佳检测底液为0.1 mol/L Na2HPO4-Na H2PO4缓冲溶液（p H 6.0）。在最优检测条件下,DA的检测线性范围为5.0×10-8~2.0×10-4mol/L,检出限低至1.0×10-8mol/L。DA电化学传感器具有良好的稳定性和重现性,灵敏度高,选择性好。将该传感器用于多巴胺注射液中DA含量的测定,结果满意。A poly（ bromophenol blue）- graphene（ PBPB- GO） composite film modified glassy carbon electrode（ GCE） was fabricated through a simple and controllable dropping and in situ electropolymerizing method,which was denoted as a DA electrochemical sensor. The result indicated that PBPB- GO composite film had a good catalytic effect on the electrochemical reduction of DA. The conductivities of bare GCE, GO/GCE, PBPB/GCE and PBPB/GO/GCE film were characterized through electrochemical impedance spectroscopy. The comparison results showed that the PBPB/GO /GCE had a lower resistance. Moreover,scanning electron microscopy was used to characterize the surface morphology of bare GO,GO/GCE and PBPB/GO/GCE,and the results indicated that PBPB-GO film had a loose and porous structure,which was beneficial to the enrichment of DA. Furthermore,the electrochemical reaction mechanism of DA on the PBPB/GO/GCE was studied and the results indicated that the electrochemical reaction of DA on the PBPB/GO/GCE was an adsorption controlled and proton participating process. The detection conditions were optimized,and the optimal electropolymerization cycles number was 15,the optimal quantity of GO（ 2 mg/m L） was 2 μL,and the op-timal electrolyte solution was 0. 1 mol/L phosphate buffer solution（ p H 6. 0）. Under the optimal detection conditions,a wide linear range over DA concentration of 5. 0 × 10- 8- 2. 0 × 10- 4mol/L was obtained with a low detection limit of 1. 0 × 10- 8mol/L. The DA electrochemical sensor showed good stability and reproducibility,high sensitivity and good selectivity,and was successfully applied in the detection of DA in dopamine injection.

关 键 词：聚溴酚蓝 石墨烯 玻碳电极 多巴胺 电化学传感器 

分 类 号：O657.1[理学—分析化学] O623.732[理学—化学]