Revolutionizing HPV Detection: Unveiling a Novel Electrochemical Immunosensor for Ultra-Sensitive HPV16 E7 Oncoprotein Detection Based on Gold-Graphitic Carbon Nitride Nanocomposite

Abstract

Cervical cancer (CC), a significant contributor to the mortality of females globally, manifests an annual incidence of 500,000 cases and is predominantly linked to the human papillomavirus (HPV) infection. The pressing demand for affordable and user-friendly assays for CC detection is highlighted by the limited availability and dependability of diagnostic screening tools, especially in developing countries. In response to the critical need for enhanced cervical cancer diagnostics, we present an innovative electrochemical immunosensor designed for the selective detection of the HPV 16-E7 oncoprotein. The immunosensing platform is constructed from a gold-graphitic carbon nitride (Au-g-C3N4) nanocomposite, with antibodies immobilized through a physical adsorption process onto the sensing platform. Employing Square Wave Voltammetry (SWV), we systematically evaluated the antigen-antibody interaction, achieving ultrasensitive detection of E7 with ferric/ferrocyanide. The linear detection range of the proposed sensor for E7 antigen is 0.01 fg ml−1 to 1 ng ml−1, assuming ideal conditions and an impressive Limit of Detection (LOD) of 0.0065 fg ml−1. The accuracy of the proposed immunosensor was effectively evaluated in contrast to Enzyme linked immunosorbent assay (ELISA). Finally, the proposed immunosensor exhibited favourable selectivity, sensitivity, and reproducibility upon introduction to clinical samples, thereby validating its potential suitability for point-of-care testing aimed at the timely detection of CC.