Electrochemiluminescence immunosensor based on Cu3(PO4)2 hybrid nanoflowers as a novel luminophore for the sensitive detection of prostate-specific antigen.

ABSTRACT

Copper phosphate hybrid nanoflowers (Cu3(PO4)2HNFs) were demonstrated to produce cathodic ECL emission in the presence of potassium persulfate (K2S2O8) and then used as a carrier due to their large specific surface area. AgNPs modified on Cu3(PO4)2HNFs provided more binding sites for immobilizing secondary antibodies and accelerating the electron transfer rate to enhance the ECL signal. In addition, FONDs-Au was used to capture primary antibodies due to its good biocompatibility and large specific surface area. A sandwich electrochemiluminescence (ECL) immunosensor based on copper phosphate hybrid nanoflower/Ag nanoparticle (Cu3(PO4)2HNFs@Ag) composite and Au NPs-functionalized Fe2O3 nanodendrites (FONDs-Au) was constructed to detect prostate-specific antigen (PSA) in real samples. Under optimal conditions, the constructed sandwich ECL immunosensor was sensitive to PSA with a detection limit of 0.037 pg/mL (S/N = 3), a linear detection concentration range of 0.0001-50 ng/mL, and a recovery range of 97.33-102.5%. This immunosensor is expected to provide a method to detect PSA or other biomarkers.