A novel method for polyaniline synthesis with the immobilized horseradish peroxidase enzyme

A novel method for the synthesis of a water-soluble polyaniline with the immobilized horseradish peroxidase (HRP) enzyme is presented. The enzyme HRP is immobilized on chitosan powder by a simple glutaraldehyde bridge method. The immobilized HRP is an effective catalyst for the oxidative polymerization of aniline in the presence of hydrogen peroxide at room temperature. The overall reaction is sensitive to solution pH and hydrogen peroxide concentration. The UV-VIS absorption spectra of the products are similar to that of polyaniline obtained with an HRP solution as a catalyst, and they display a distinct absorption peak at 750 nm at pH 4.0. The immobilized HRP is stable and remains active after being stored in pH 6.0 buffer solution at room temperature for more than 72 h. Published by Elsevier Science B.V.