Electrodes modified with polyaminophenols:: Immobilization of purines and pyrimidines

This work describes the preparation of polymers potentiodynamically formed on surface of graphite electrode by anodic oxidation of 2, 3, or 4-aminophenol monomers, as well as incorporation and detection of purine and pyrimidine bases on these modified electrodes. The electrochemical behavior of the formed films was studied by cyclic voltammetry and electrochemical impedance spectroscopy. These analyses indicate that poly-4-aminophenol presents the highest charge transfer rate. The surface morphology was studied by SEM and AFM. These analyses showed that the polymers present globular morphology. The immobilization and detection of purines and pyrimidines on graphite electrodes modified with poly-aminophenols was studied by differential pulse voltammetry. It was possible to show, for the first time, that the oxidation of purine and pyrimidine bases and their mixtures takes place on modified electrodes covered with polymeric films.