Dopamine/mucin-1 functionalized electro-active carbon nanotubes as a probe for direct competitive electrochemical immunosensing of breast cancer biomarker

Abstract Mucin-1 (MUC-1) is associated with a broad range of human epithelia including gastric, lung and colorectal. In this work, a direct competitive electrochemical immunosensor based on gelatin modified transduction platform was designed. Dopamine (DA)/mucin-1 functionalized electro-active carbon nanotubes were employed as signal generating probes in the construction of electrochemical immunosensor for early stage diagnosis of breast cancer. The gelatin modified electrode served as a support to immobilize antibody (anti-MUC-1), while electrochemical response of functionalized electro-active carbon nano probes was used for quantitative measurement of MUC-1. Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) were carried out to characterize the transduction surface at different fabrication steps. The developed immunosensor permitted the detection of MUC-1 in the linear range of 0.05−940 U/mL, with a detection limit (LOD) of 0.01 U/mL. The immunosensor showed recovery values in the range of 96% for human serum sample analysis, demonstrating its practical applicability.