A high-performance nanohybrid impedimetric platform for early cancer detection via c-Myc oncoprotein sensing

Widespread and precise detection of oncogenic biomarkers is critical for timely cancer diagnosis and effective treatment. The Myc oncogene is widely deregulated across multiple malignancies, turning it a compelling target for pan-cancer detection. Here, we rationally engineered an electrochemical immunosensor integrated with nitrogen-doped multiwalled carbon nanotubes (MWCNTs) decorated by silver nanoparticles (AgNPs) for achieving rapid and ultrasensitive detection of Myc. Nitrogen doping introduced electron dense regions, to facilitate uniform anchoring of nanoparticles with enhanced interfacial charge transfer. Anti-Myc as a biorecognition element is covalently immobilized over the modified electrode surface with the help of a biocompatible antibody linker. The synergistically biocompatible nanostructure significantly reduced the charge transfer resistance. This enables efficient signal transduction upon antigen recognition in spiked human plasma samples. The biosensor demonstrated a wider linear range from 27.5 pg mL^-1 to 5 ng mL^-1 and a detection limit (LOD) of 0.19 pg mL^-1 validated electrochemically through cyclic voltammetry and impedance spectroscopy. Additionally, atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to analyze morphological changes during each step of electrode fabrication, while FTIR and Raman spectroscopy confirmed antibody immobilization on the sensor surface. The straight forward layer-by-layer deposition method has simplified the complex fabrication process, improved long-term storage stability, and scalability. This sustainable, high-performance sensing platform offers a promising route towards a portable, real-time point-of-care (POC) detection of oncogene biomarkers for early cancer screening.