Three-dimensional Au nanoparticles/nano-poly(3,4-ethylene dioxythiophene)- graphene aerogel nanocomposite: A high-performance electrochemical immunosensing platform for prostate specific antigen detection

Conductive poly(3,4-ethylenedioxythiophene) (PEDOT) composites have emerged as potential candidates for electrochemical biosensors, however, the sensing performance was mainly relied on their structure and composition. In this work, a novel three-dimensional (3D) structural nano-PEDOT-graphene aerogel (nano-PEDOT-GA) composite was designed via the in-situ polymerization of nano-PEDOT on porous 3D GA. SEM revealed that the introduction of GA could induce the growth of worm-like PEDOT. Subsequently, Au nanoparticles (AuNPs) were directed to nano-PEDOT-GA surface by electrodeposition method. Featuring the excellent biocompatibility, high specific surface area and good conductivity of AuNPs/nano-PEDOT-GA, a highly sensitive label-free immunosensor was developed using AuNPs/nano-PEDOT-GA as signal amplification platform for detecting prostate specific antigen (PSA). Under the optimal conditions, the fabricated immunosensor presented a good linear in the analytical range of 0.0001–50 ng mL −1 with a low detection limit of 0.03 pg mL −1 (S/N = 3), high selectivity against other serum interfering substance and good stability and reproducibility, which provides a promising platform for the clinical immunoassay of PSA.