Cu 2 O@PdAg-quenched CdS@CeO 2 heterostructure electrochemiluminescence immunosensor for determination of prostate-specific antigen

Based on the resonance energy transfer between CdS@CeO 2 and Cu 2 O@PdAg, a quenching immunosensor for sensitive detection of prostate specific antigen (PSA) was constructed. The CdS@CeO 2 heterostructure was obtained by in situ growth of CeO 2 particles on the surface of CdS nanorods, and stable cathodic ECL emission was achieved using K 2 S 2 O 8 as coreactant. Cu 2 O@PdAg was composed of Cu 2 O 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 2 , 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 −1 ~ 100 ng·mL −1 , with a detection limit of 5.6 fg·mL −1 . 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. Graphical Abstract