中文摘要：

采用自组装方法,将聚二烯丙基二甲基氯化铵（PDDA）功能化的金纳米颗粒（Au NPs）负载于多壁碳纳米管（MWCNTs）-还原型氧化石墨烯（r GO）夹层,再涂覆于玻碳电极（GCE）上,制备了纳米复合膜修饰电极MWCNTs-r GO/PDDA-Au NPs/GCE.采用透射电子显微镜（TEM）和紫外-可见光谱（UV-Vis）对修饰膜的形貌及结构进行表征.探讨了其对莱克多巴胺（Rac）的循环伏安行为,结果表明MWCNTs-r GO/PDDA-Au NPs纳米复合物对Rac表现出显著的电催化氧化特性.采用差分脉冲伏安法测得该复合膜修饰电极对Rac检测的线性范围为0.036～4.5μmol/L,检出限为6.35 nmol/L（S/N≥3）,且显示出良好的抗干扰能力、稳定性及重现性.采用该方法检测猪血清及猪尿样中的Rac,回收率达95.4%～105.9%,表明该复合膜修饰电极对实际样品中Rac的检测具有潜在应用价值.

英文摘要：

A nanocomposite film of MWCNTs-r GO/PDDA-Au NPs was fabricated through self-assembly method. The surface morphologies of different composite modified glassy carbon electrodes（ GCEs） were characterized by means of TEM and UV-Vis spectroscopy,and the cyclic voltammetry behaviors of ractopamine（ Rac） were investigated. The results showed that the MWCNTs-r GO/PDDA-Au NPs composite exhibited significantly electrocatalytic activity towards oxidation of Rac. The results of differential pulse voltammetry showed that the electrode possessed a linear range of 0. 036—4. 5 μmol/L and a detection limit of 6. 35 nmol/L（ S/N≥3） with good stability,reproducibility and selectivity. The electrode can be well applied to determination of Rac in pork serum and pork urine with a recovery rate of 95. 4% —105. 9%,suggesting a potential application for actual samples in food security field.