The Study on Reaction Kinetics Based on a New System of the Horseradish Peroxidase Catalyting the Oxidation of o-phenylenediamine by H2O2

In this paper, we study the enzyme catalysis reaction kinetics that 2,3-diaminophenazine compound was synthesized with the horseradish peroxidase catalyzing reaction of H2O2 oxidizing o-phenylemediamine. First, the product of oxidation of o-phenylenediamine (OPD) by H2O2 catalyzed and by hotseradish peroxidase (HRP) was synthesized. The finest reaction conditions (acid degree, temperature, OPD,H2O2,HRP various molar ratio) were selected. The reaction conditions and the product were determined by UV-absorption spectrum, IR and element analysis. The results showed that the product is 2,3-diaminophenazine. Secondly,the reaction order of OPD-H2O2-HRP system and the rate constant were studied by using ultraviolet spectrophotometry based on Michaelis-Menten equation. The finest conditions λmax= 446.3 nm, pH = 4.85, t = 22°C were selected, a series experiments were done. Experimental results showed that this is an one reactant reaction determined by the experiment and theory, and derived Km = 6.02 × 10-3 mol*L-1 and vm = 7.2× 10-2 ΔA*min-1.