▎ 摘　　要

In this work, electrochemiluminescence (ECL) luminophor Ru(bpy)(3)(2+) was encapsulated in 3D CuNi oxalate and the synthesized metal-inorganic frameworks {[Ru(bpy)(3)][Cu2xNi2(1-x)(ox)(3)]}(n) (Ru/Cu/Ni) exhibited excellent and stable ECL signals, which could be decreased by polyethylenimine capped graphene oxide (GO PEI). Based on this, a new sandwich ECL immunosensor was developed for detection of carcinoembryonic antigen (CEA). To capture primary antibody and second antibody more simply and efficiently, Ag nanoparticles were doped with Ru/Cu/Ni and GO-PEI. After a sandwich-type immunoreaction, a remarkable decrease of ECL signal was observed due to the release of Ru(bpy)(3)(2+) which was caused by the coordination between PEI and metal ions. Under the optimization of determination conditions, a linear response range for CEA from 0.1 pg mL(-1) to 100 ng mL(-1) was obtained, and the detection limit was calculated to be 0.027 pg mL(-1) (S/N=3). The prepared CEA immunosensor displayed high sensitivity, excellent stability and good specificity.