Peptide Tritrpticin Interaction onto Chemically Modified Graphene Oxide Paste Electrode

Abstract

The simple strategy to prepare Chemically Modified Carbon Paste Electrodes (CPE) by using Graphene Oxide (GO) was made to promote the desired interaction of antimicrobial Peptide Tritrpticin (TRP3) on them. This interaction was chosen considering the important study of biological sensors remarkable by GO and TRP3. The Interaction of CPEGO with TRP3 was characterized by FTIR and Electrochemical Techniques, that employed Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The FTIR reveals some modifications of GO and GOTRP3 samples, with bands identified by functional polar groups and stretching mode C-N. CV results confirmed that GO promoted the interaction of TRP3 on the Carbon Paste Electrode by TRP3 adsorption on its oxidated defects sites with amplification current response. The oxidation peak potential shows a negative shift around 20 mV in the ferricyanide potassium presence, which indicates electron transfer between the GO and TRP3 was facilitated. EIS measurements show the interaction of TRP3 with GO with smaller electron transfer resistance as the almost linear portion of the Nyquist plot in comparison to CPE. The results indicate a Chemically Modified Carbon Paste Electrode with GO and TRP3 interactions is a potential electrode designed for biological sensor or drug delivery applications.