Development of proof of concept for prostate cancer detection: an electrochemical immunosensor based on fullerene-C60 and copper nanoparticles composite film as diagnostic tool

Screening of Prostate-specific antigen (PSA) in human blood is the most common approach to diagnose prostate cancer. The joint application of biology and electrochemistry has shown a tremendous rise in research towards the development of electrochemical diagnostic tools for various diseases. The present study demonstrates the development of an effective immunosensing platform incorporating hydroquinone (HQ) immobilized, fullerene-C60 and copper nanoparticles (CuNPs) composite film on glassy carbon electrode (HQ@CuNPs-reduced-fullerene-C60/GCE) for the selective, quick and trace detection of PSA. In order to fabricate immunosensor sequential immobilization of primary antibody (Ab1), blocking agent (bovine serum albumin (BSA)), antigen (prostate-specific antigen (PSA)) and secondary antibody (Ab2) tagged with horseradish peroxide (HRP) was carried out on HQ@CuNPs-reduced-fullerene-C60/GCE. Electrochemical characterization and the signal response of immunosensor were tested using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Due to the synergetic effect of fullerene-C60 and CuNPs, the novel nanocomposite film exhibited excellent catalytic activity towards hydrogen peroxide (H2O2) reduction for greatly amplified immunosensing signals. HQ@CuNPs-fullerene-C60/GCE exhibited a well-defined redox peak and accelerated electrochemical reduction of H2O2 without any interference of dissolved oxygen and false-positive result in phosphate buffer solution (PBS) at pH 7.0. The parameters influencing the electrochemical response were optimized. Under the optimized conditions, wide linearity between PSA concentrations and current responses ranging from 0.005 ng/mL to 20 ng/mL with the lower detection limit of 0.002 ng/mL was obtained at the proposed immunosensor. The clinical applicability of the proposed immunosensor was successfully tested in serum and urine samples. Results revealed that the proposed immunosensor may create new boundaries in the identification of PSA in human blood samples. Illustration of PSA sensing in serum sample via paper based immunosensor as a proof of concept. [Display omitted] •A novel proof of concept was developed for the detection of prostate-specific antigen (PSA) in serum samples.•HQ@CuNPs-fullerene-C60/GCE sensing platform was designed to fabricate immunosensor.•The fabricated immunosensor exhibited excellent sensitivity, special selectivity, and long-term stability.•The immunosensor showed excellent limit of det