Electropolymerization of Aniline on the Pre-Passive Substrate and its Application for Preparation of Enzyme-Modified Electrode

Abstract

The electrodeposition of polyaniline films on iron substrate electrode from an aqueous acidic medium is studied to preparation of enzyme-modified electrode. The electrochemical polymerization of aniline was carried out on a pre-passive Fe electrode. Existence of a pre-passive film on the substrate electrode before electropolymerization is effective on the formation of electroactive film on electrode surface. Chronopotentiometric measurements were utilized for investigation of the influence of the pre-passive substrate on the electropolymerization process. Enzyme-modified electrodes were prepared using the growth film. Two different bioelectrodes were fabricated by using Fe electrode and pre-passive Fe electrode and were compared. Experimental results illustrate that the polyaniline film formed on the pre-passive Fe electrode is highly stable and consequently improves stability of the enzyme-modified electrode.

Keywords: polyaniline, pre-passive, electropolymerization, thin films, Fe substrate, biosensor