The nanocomposite of polydopamine and Ag nanoparticles (PDA-AgNPs) provided an effective matrix for the immobilization of primary antibody (Ab1).
Carbon quantum dots (CQDs), the electrochemiluminescence material, were immobilized on the poly(ethylenimine) functionalized graphene oxide (PEI-GO) to link secondary antibody (Ab2).
The ECL signals of CQDs were greatly amplified under the synergistic effect of AgNPs, polydopamine, AuNPs and PEI-GO.
The proposed ECL immunosensor can be used for the detection of CEA in real human serum samples.