CuO@PdAg-quenched CdS@CeO heterostructure electrochemiluminescence immunosensor for determination of prostate-specific antigen.

Based on the resonance energy transfer between CdS@CeO and CuO@PdAg, a quenching immunosensor for sensitive detection of prostate specific antigen (PSA) was constructed. The CdS@CeO heterostructure was obtained by in situ growth of CeO particles on the surface of CdS nanorods, and stable cathodic ECL emission was achieved using KSO as coreactant. CuO@PdAg was composed of CuO with tetradecahedral structure and bimetallic PdAg nanospheres and has a UV-V is absorption range between 600 and 800 nm. It overlaps with the ECL emission spectrum of CdS@CeO, realizing the effective quenching of the ECL signal, which provides feasibility for subsequent practical application. The immunosensor exhibited good linearity in the concentration range 10 fg·mL ~ 100 ng·mL, with a detection limit of 5.6 fg·mL. In sample analysis, the recoveries were 99.8-101%, and the relative standard deviation (RSD) was 0.85-1.6% showing great potential and development value for the sensitive detection of prostate cancer.