Functionalization of MWCNTs with Ferrocene-poly(p-phenylene) and Effect on Electrochemical Properties: Application as a Sensing Platform

MWCNTs have been dispersed with modified ferrocene-poly(para-phenylene) by π staking interaction to improve dispersion of MWCNTS in organic solution. Such interaction has been demonstrated through electrochemical and chemical characterization of the composite. A layer based on the formed composite (MWCNTs/Fc-PPP) has been deposited on a gold surface and the electrochemical properties of the redox reaction have been studied through Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). We demonstrate that such association of the Fc-PPP to MWCNTs allows their functionalization and introduction of redox markers which could be used as a platform for a sensing application. The proof of the concept has been demonstrated through DNA immobilization and detection of specific oligonucleotide probe of hepatitis C. The properties of the DNA biosensor construction were followed by redox properties of immobilized redox markers. The nanocomposite (MWCNTs/Fc-PPP) modified by DNA probes demonstrates a sensitivity to DNA hybridization with a detection limit of 1.6 pM and a wide linear range of detection from 1 fM to 100 pM taking advantage from the large surface of MWCNTs and their electronic properties.