Abstract: Abstract A novel electrochemical multiplexed immunoassay was designed for simultaneous determination of alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) using recombinant apoferritin-encoded metallic nanoparticles (rApo-M) as labels and dual-template magnetic molecularly imprinted polymers (MMIPs) as capture probes. The labels were prepared by loading recombinant apoferritin (r-Apo) and separately immobilize primary antibodies (anti-AFP and anti-CEA) via Au nanoparticles of in site growth on graphene (G). The capture probes were synthesized by self-polymerization of dopamine (DA) on the Fe3O4 nanoparticles (Fe3O4 NPs) and using AFP and CEA as the template proteins, which were used to enrich the targets simultaneously. After a sandwich-type immunoreaction, the labels were captured to the surface of MMIPs. The subsequent electrochemical stripping analysis of the metal components from the immunocomplex provide a means for quantification of targets based on the peak currents of Cd and Pb. Experimental results showed the immunoassay enabled the simultaneous determination of AFP and CEA in a single run with wide dynamic ranges of 0.001-5 ng mL-1. And the detection limits of AFP and CEA were 0.3 and 0.35 pg mL-1 (S/N=3), respectively. These results suggested that the proposed multiplexed immunoassay would be applied for clinical screening of other biomarkers
Template and target information: protein, dual-template, alpha-fetoprotein, AFP, carcinoembryonic antigen, CEA
Author keywords: Multiplexed immunoassay, Recombinant apoferritin, Graphene-Au, Dual-template magnetic molecularly imprinted polymers