Abstract / Summary
Ovarian cancer continues to be one of the most aggressive gynecological malignancies, largely due to its silent progression, absence of robust early diagnostic markers, and limited screening options. Among emerging molecular regulators, microRNA-155 (miRNA-155) has gained significant attention as an oncogenic biomolecule implicated in tumor growth, immune response regulation, epithelial–mesenchymal transition, and the development of chemoresistance in ovarian cancer. Conventional diagnostic techniques such as qRT-PCR, northern blotting, and next-generation sequencing, although highly accurate, are often restricted by high operational costs, complex sample preparation, and limited feasibility for rapid or point-of-care applications. To address these limitations, we propose an advanced hybrid biosensing system based on polypyrrole-functionalized Ti₃C₂Tₓ MXene (PPy–MXene) electrodes coupled with ferrocene-assisted redox cycling for signal amplification, along with artificial intelligence (AI)-enabled electrochemical signal interpretation. This integrated platform is designed for highly sensitive quantification of miRNA-155 in ovarian cancer plasma samples. The PPy–MXene composite offers exceptional electrical conductivity, high electroactive surface area, and improved nucleic acid immobilization efficiency. Meanwhile, ferrocene mediates efficient electron transfer through reversible Fc²⁺/Fc³⁺ redox cycling, significantly enhancing signal output. The incorporation of AI-based models enables effective correction of background noise, signal drift, and biological variability, improving overall analytical reliability. The developed biosensor demonstrates an ultra-low detection limit of 0.3 fM, a broad linear response range, and strong agreement with qRT-PCR results (R² = 0.98).