Electrochemical DNA Biosensors for the Detection of TP53 Gene Mutation Based on MWCNT and Gold Nanoparticles Embedded in Polypyrrole

A novel platform has been developed for the sensitive label-free detection of mutation in the TP53 gene, one of the most prominent genes in cancer research. The platform is based on the electrochemical properties of functionalized multi-walled carbon nanotubes (f-MWCNTs), gold nanoparticles (AuNPs), and polypyrrole (PPy). The microscopic structure and morphology of the prepared films on an ITO electrode surface were characterized using X-ray diffractometry (XRD), field emission scanning electron microscopy (FE-SEM), and Fourier transform infrared (FTIR). The hybridization events specific to the TP53 gene were monitored using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The modified electrode, which incorporates vertically aligned f-MWCNTs arrays and AuNPs, exhibited enhanced probe DNA attachment density, improving the sensitivity of the DNA sensor. The combination of AuNPs/PPy with an in-situ produced f-MWCNTs array provides a viable strategy for developing a highly sensitive biosensor for fast mutation detection in human cancer types.