Investigation on electrochemical behavior of peroxidase enzyme in the presence of hydrogen peroxide and 5-aminosalicylic acid

Abstract

The electrochemical behavior of the enzyme peroxidase (HRP) was investigated using the hydrogen peroxide as enzymatic substrate and the 5-aminosalicylic acid (5-ASA) as mediator of electrons on graphite electrodes. Several parameters were optimized, namely, the applied potential to the amperometric technique fixed in -0.125V, the 0.1 mol L-1phosphate-citrate buffer at pH 5.0 as supporting electrolyte and the proportion between the 5-ASA and H2O2in 1:7, among others. It was observed the catalysis of the oxidation reaction of the H2O2in the presence of the enzyme HRP and 5- ASA. The oxidation product was reduced in the electrode surface, evidencing a significant increase in the intensity of the cathodic current.