基于丝网印刷电极的甲胎蛋白电化学免疫传感器  

Disposable Screen-printed Electrodes for High Sensitive Electrochemical Immunosensing of Alpha-fetoprotein

作　　者：毕可 施晓文[1] 杜予民[1] 

机构地区：[1]武汉大学资源与环境科学学院,湖北武汉430079

出　　处：《分析科学学报》2017年第2期159-164,共6页Journal of Analytical Science

基　　金：国家自然科学基金(No.21007049)

摘　　要：报道了一种基于金纳米粒子(AuNPs)双重信号放大的高灵敏电化学免疫传感器,并应用于肝癌标志物甲胎蛋白(AFP)的检测。通过在丝网印刷电极(SPE)表面电沉积AuNPs提高电极的重现性,利用AuNPs的吸附作用固定AFP抗体,用于捕获样品中的待测AFP抗原,并进一步与固定了辣根过氧化物酶(HRP)标记检测抗体的纳米金免疫探针发生特异性结合,所形成的夹心免疫复合物可以催化底物得到响应电流。用扫描电镜(SEM)和微分脉冲伏安法(DPV)等技术研究电极组装过程以及电极的化学性质,讨论了影响免疫传感器性能的因素。在最优实验条件下,传感器的峰电流信号与AFP浓度在2.5~30ng/mL范围内呈良好的线性关系,检出限为0.16ng/mL。该传感器具有灵敏度高、成本低、仪器体积小的优点,具有较好的应用前景。A disposable electrochemical immunosensor for high sensitive detection of alpha-fetoprotein（AFP）based on the dual-amplification effects of gold nanoparticles（AuNPs）by using disposable screenprinted electrodes（SPE）was reported.To construct the sensor,anti-AFP antibodies were firstly immobilized on the surface of SPE modified with AuNPs,which were in situ formed by cyclic voltammetry.Then,AFP antigens were captured onto the sensor via immunoreactions,followed by further capture and immobilization of HRP-labeled AuNPs immunoprobes,which formed a sandwiched immunosensing structure.Finally,the resulting immunocomplex catalyzed the reduction of hydrogen peroxide（H2O2）using hydroquinone（HQ）as an electron mediator to generate reduction currents.Differential pulse voltammetry（DPV）and scanning electron microscopy（SEM）were used to characterize the construction process and the analytical performance of the sensor.The reduction peak current was linear with the concentration of AFP in the range of 2.5-30ng/mL under optimized conditions,along with a low detection limit of 0.16ng/mL.The proposed immunosensor provided a highly sensitive,lowcost,simple and practical method for AFP detection.

关 键 词：丝网印刷电极 甲胎蛋白(AFP) 电化学免疫传感器 

分 类 号：O657.1[理学—分析化学]