Early Warning of Drug-Induced Cardiotoxicity: Quantitative Analysis of Mfn2 Biomarker via Electrochemical Immunosensing Technology

Drug-induced cardiotoxicity (DIC) poses a significant challenge in both drug development and clinical practice, making early and accurate assessment crucial. Existing studies have shown that mitochondrial fusion mediated by mitochondrial fusion protein 2 (Mfn2) is closely associated with DIC, and that up-regulation of Mfn2 reduces drug-induced cardiomyocyte damage and apoptosis, suggesting that Mfn2 could be a potential biomarker for early warning assessment of DIC. Due to the defects of cumbersome operation, limited sensitivity, high cost, and difficulty in popularization of existing detection technologies, this study has developed a novel electrochemical immunosensor for highly sensitive detection of Mfn2, enabling early risk assessment of DIC. The sensor utilizes a composite material consisting of sodium titanate nanorods (prepared via MXene oxidation and alkalization) and multi-walled carbon nanotubes (M-NTO-MWCNT) as the sensing substrate. The M-NTO component, with its unique nanorod structure, abundant active sites, and high surface area, significantly enhances sensitivity and provides ample antibody immobilization sites. Meanwhile, MWCNTs improve electron transfer efficiency and selectivity due to their superior conductivity and interconnected network. Under optimized conditions, the sensor achieves a detection limit as low as 1.85 ng mL ^− 1 and a linear range of 9.38×10 ^− 1 –2.40×10 ² ng mL⁻¹. Serum sample testing demonstrated excellent reproducibility (RSD < 5%), outperforming conventional ELISA methods. This study provides a new rapid and portable test solution for the early warning of drug-derived cardiotoxicity, and provides technical support and scientific reference for the safety assessment of new drug development.