一种基于纳米金／石墨烯／普鲁士蓝（PB）修饰玻碳电极非标记免疫传感器

采用电聚合的方法将普鲁士蓝（PBl聚合在玻碳电极表面，再将石墨烯修饰在PB上面，然后再采用电沉积的方法将HAuCL直接还原成纳米金粒子，沉积在石墨烯表面，最后将羊抗人IgG抗体直接固定于该修饰的玻碳电极表面，制备了用于人IgG抗原检测的非标记电化学免疫传感器。利用循环伏安法和交流阻抗研究了修饰电极表面的电化学特性，用差分脉冲伏安法对人IgG抗原进行了测定。实验表明，此免疫传感器在含不同浓度人IgG的PBS溶液（pH6．98）中测定，响应电流与人IgG浓度在5．55～455．5ng／mL范围内有良好的线性关系，其相关系数r=0．9926，检测限为0．015ng／mL（S／N=3）。该免疫传感器具有制备简单、响应时间快（5min）、稳定性好等特点。

A label-free immunosensor based on gold nanoparticles/graphene/PB modified glass carbon electrode

A highly sensitive label-free electrochemical immunosensor for the determination of human IgG based on a glassy carbon electrode modified with GNPs-graphene and prussian blue(PB) by electrpolymerization was developed.IgG antibody was directly absorbed on the modified electrode surface.The electrochemical behaviors of the modified electrodes were investigated by cyclic votammetry(CV) and ac impedance.The human IgG was determinated by differential pulse voltammetry(DPV).It was found that there was good linear between response current and concentration of human IgG antigen over a range from 5.55 to 455.5 ng/mL with the correlation coefficient of 0.992 6 with the detection of 0.015 ng/mL(S/N=3).The resulting immunosensor exhibited good convenient,fast response time(5 min) and long-term stability due to without reagent of signal amplification.