School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China.
School of Information and Communication, Guilin University of Electronic Technology, Guilin, 541004, China.
Mikrochim Acta. 2020 Sep 29;187(10):584. doi: 10.1007/s00604-020-04559-2.
Using gold and magnetic nanoparticles co-decorated reduced graphene oxide-tetraethylenepentamine (rGO-TEPA/Au-MNPs) as the magnetic platform for capturing the primary antibody (Ab), separation and preconcentration of immunocomplex, a novel homogeneous electrochemical immunosensor was successfully developed. The newly prepared magnetic rGO-TEPA/Au-MNPs, compared with MNPs, exhibited better stability and enhanced electrical conductivity attributed to rGO-TEPA, and showed higher biorecognition efficiency due to AuNPs. In addition, Au@PtNPs were prepared and modified with secondary antibody (Ab) as an efficient signal probe for signal readout. Using carcinoembryonic antigen (CEA) as a model analyte, the prepared immunosensor demonstrated satisfactory properties like high stability, good repeatability and selectivity, wide linear range (5.0 pg mL~200.0 ng mL) as well as low detection limit (1.42 pg mL). The homogenous electrochemical immunosensor was applied to the detection of CEA in human serum and was found to exhibit good correlation with the reference method. Thus, the proposed rGO-TEPA/Au-MNPs-based homogenous immunoassay platform might open up a new way for biomarker diagnosis. Graphical Abstract.
采用金和磁性纳米粒子共修饰的还原氧化石墨烯-四乙烯五胺（rGO-TEPA/Au-MNPs）作为捕获一抗（Ab）、免疫复合物分离和预浓缩的磁性平台，成功研制了一种新型均相电化学免疫传感器。与 MNPs 相比，新制备的磁性 rGO-TEPA/Au-MNPs 由于 rGO-TEPA 的存在表现出更好的稳定性和增强的导电性，并由于 AuNPs 的存在表现出更高的生物识别效率。此外，还制备了 Au@PtNPs 并修饰了二抗（Ab）作为信号读出的有效信号探针。以癌胚抗原（CEA）为模型分析物，所制备的免疫传感器表现出令人满意的性能，如高稳定性、良好的重复性和选择性、宽线性范围（5.0 pg mL~200.0 ng mL）和低检测限（1.42 pg mL）。均相电化学免疫传感器用于检测人血清中的 CEA，与参考方法具有良好的相关性。因此，基于 rGO-TEPA/Au-MNPs 的均相免疫分析平台可能为生物标志物诊断开辟新途径。
