Fabrication of Immunosensor Based on Polyaniline, Fullerene‐C<sub>60</sub> and Palladium Nanoparticles Nanocomposite: An Electrochemical Detection Tool for Prostate Cancer
Lakkavarapu Suresh, Jayakumar Singh Bondili, Pradeep Kumar Brahman
Abstract
Abstract Present work demonstrates the fabrication of new and facile sandwich‐type electrochemical immunosensor based on palladium nanoparticles (PdNPs), polyaniline (PANI) and fullerene‐C 60 nanocomposite film modified glassy carbon electrode (PdNP@PANI‐C 60 /GCE) for ultrasensitive detection of Prostate‐specific antigen (PSA) biomarker. PdNP@PANI‐C 60 was electrochemically synthesized on GCE and used as an electroactive substrate. PdNP@PANI‐C 60 was characterized by scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDS), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Primary antibody anti‐PSA (Ab1) was covalently immobilized on PdNP@PANI‐C 60 /GCE using NHS/EDC linkers. In the presence of PSA antigen, horseradish peroxidase secondary antibody (HRP‐Ab2) was brought into the surface of the electrode, developing stable amplified signals of H 2 O 2 reduction. Under the optimal conditions, a linear curve for determination of PSA at the proposed immunosensor was 1.6×10 −4 ng.mL −1 to 38 ng.mL −1 with a limit of detection (LOD) of 1.95×10 −5 ng.mL −1 . The proposed immunosensor was successfully validated in serum and urine samples towards PSA detection with satisfactory and acceptable results.