A sandwich-type electrochemical immunosensor for detecting CEA based on CeO2-MoS2 absorbed Pb2+

A sandwich-type immunosensor for detecting the concentration of carcinoembryonic antigen (CEA) was prepared. In this work, gold nanoparticles (Au NPs) were used as platform to attach more primary antibody (Ab 1 ) due to excellent electrical conductivity and good biocompatibility. Molybdenum disulfide-Cerium oxide (CeO 2 -MoS 2 ) nanohybrid was used as a carrier to absorb lead ions (Pb 2+ ) and the second antibody (Ab 2 ). CeO 2 -MoS 2 -Pb 2+ -Ab 2 was used as a nanoprobe to detect CEA antigen. Under optimal conditions, square wave voltammetry (SWV) successfully displayed the electrical signal of Pb 2+ . The designed electrochemical immunosensor has excellent analytical performance. In addition, the detection range was 0.001–80 ng/mL and the minimum detection limit was 0.3 pg/mL (S/N = 3), which had good selectivity and stability. Finally, the proposed immunosensor successfully detected the concentration of CEA in the serum of the sample, which provided a feasible method for CEA testing.