A Label-free Electrochemical Immunosensor Based on Gold Nanoparticles-poly(ferriporphyrin-co-acrylamide)-reduced Graphene Oxide and the Application in Prostate Specific Antigen Detection

Prostate specific antigen (PSA), as a biomarker, plays important roles in early diagnosis of male prostate diseases, especially prostate cancer. In this study, a novel electrochemical probe polymer of poly(ferriporphyrin-co-acrylamide) was synthesized, by further combined with reduced graphene oxide and gold nanoparticles, and oriented immobilization of PSA antibody, a label-free electrochemical immunosensor was obtained, and then successfully applied in the determination of PSA in 10 % non-antigen serum system. The prepared biosensor expressed high selectivity toward PSA, with a LOD of 0.001 ng mL−1, a linear range of 0.01–110 ng mL−1, and a sensitivity of 15.78 µA mL ng−1. What’s more, it showed good stability, well repeatability and high selectivity in the real PSA sample detection. This work provided certain references for the design of the new electrochemical probes and the detection of tumor markers.