3D graphene/MWNTs nano-frameworks embedded Ag-Au bimetallic NPs for carcinoembryonic antigen detection

In this work, a novel electrochemical immunosensor was designed for ultrasensitive determination of carcinoembryonic antigen based on 3D-structured rGO/Ag-Au NPs. 3D-rGO-MWCNTs nanocomposites feature network structure which has a large specific surface area and excellent conductivity providing more active sites for Ag-Au bimetallic nanoparticles . At the same time, the synergistic effect of 3D-rGO-MWCNTs and Ag-Au NPs, significantly improved the electrochemical performance of the modified electrode . Due to the excellent biocompatibility of Ag-Au NPs, the antibody could be well attached to the electrode, and the immunosensor could be successfully prepared. Under the optimized conditions, the constructed immunosensor showed a wide linear range from 0.001 ng mL −1 to 80 ng mL −1 with the detection limit of 3 pg mL −1 (S/N ratio of 3). The proposed immunosensor has excellent analytical performance including good stability, reproducibility and selectivity , and was successfully applied to the detection of CEA in human serum verified its practicability.