MOF-metal nanohybrid-assisted charge transfer amplification for electrochemical biosensing of MUC1 Cancer Biomarker

Abstract

Cancer underscores the severity of a disease characterized by high mortality and complex pathophysiology; however, its early and accurate diagnosis remains insufficient. Conventional diagnostic approaches often fall short, particularly in dense tissue, being invasive, costly, and less availability. It reinforces the need for a compact, economical, and ultrasensitive assay that is operationally simple and interpretable. We present an efficient electrochemical detection platform for the cancer biomarker, Mucin 1 (MUC1). The fluorine tin oxide (FTO) surface was modified with the Iron-based metal-organic Framework (FeMOF), as-intercalated with palladium nanorods (PdNR). FeMOF was prepared using the Fe3+/Fe2+ precursors at a 1.2/1 mmol ratio and dual ligands, i.e., tetrahydroxy-1,4-benzoquinone and 2-aminobenzene-1,4-dicarboxylic acid. The antiMUC1 antibodies were immobilized on a modified electrode via p-phenylenediamine (PDA) (FTO/FeMOF@PdNR/PDA/antiMUC1Ab) and evaluated by electrochemical impedance spectroscopy (EIS) and voltammetry. The designed sensor delivered an excellent binding affinity for the MUC1 antigen. Among these techniques, the EIS method stands out for its technical performance, as evidenced by the high sensitivity (detection limit 0.074 fg/ml), quantification limit 0.24 fg/ml, and high analytical sensitivity (1.39x103 Ω/fgml-1cm-2). The negligible cross-reactivity with interferent biomolecules, rapid response (10-minute equilibrium), regenerability up to 5 cycles, high reproducibility (RSD ~1-3%), and long-term stability (up to 35 days) further validate the suitability of the proposed MUC1 immunosensor. This study presents an ultrasensitive biosensor that is compact, cost-effective, and easy for individuals at home to use after further development into a kit-based end product. Moreover, its excellent functionality in serum-spiked samples promises for next-generation clinical diagnostics.