Preparação de pasta de carbono com poli(4-aminofenol) e desenvolvimento de eletrodo de trabalho com aplicação em biossensores

Abstract

This work reports the preparation of a carbon paste based on carbon flake, carbon black, Vinisol® resin and poly (4-aminophenol) for use as a working electrode surface, with application in the biosensor area. The main objective of this study was the application of this carbon paste in the development of the working electrode with low cost materials, including a copper wire, a universal polypropylene tip, acrylic CD-ROM cover and carbon paste. The poly (4-aminophenol) was prepared by chemical oxidation of the monomer with ammonium persulfate in a ratio of 1:10 monomer: oxidant and characterized by infrared spectroscopy, rheological viscosity analysis, X-ray diffractometry, scanning electron microscopy and cyclic voltammetry. The carbon paste is composed of carbonaceous materials, a resin and poly (4-aminophenol), was prepared at room temperature under mechanical stirring and ultrasound and characterized by the same techniques used for the characterization of poly (4-aminophenol). The developed carbon paste was used as the electrode surface of a handcrafted working electrode in which low cost materials were used, among them a universal 200 μL polypropylene tip, a 1.5 mm diameter copper wire and Acrylic cover from CD-ROM. Immobilization of oligonucleotides (poly [GA] probe on the surface of the electrode and, in sequence, interaction with the complementary poly [CT] target) was carried out, confirming the occurrence of hybridization between oligonucleotides by differential pulse voltammetry, indicating that this work electrode presents potential for its application as an electrode surface for the development of electrochemical biosensors.