Abstract:

The investigation of inhibition of xanthine oxidase by allopurinol was carried out using a xanthine biosensor, which was obtained using the polyaniline film as a support material. The experimental results indicated that significant inhibition could be produced by allopurinol but this inhibition was reversible. The apprent Michaelis-Menten constant (K’m) of the immobilized xanthine oxidase increased in the presence of allopurinol, but the maximum rate of the enzyme catalyzed reaction was not affected by allopurinol. This indicated that allopurinol is a reversible competitive inhibitor of xanthine oxidase. The optimum pH of the immobilized enzyme was not affected, and the activation energy of the enzyme catalyzed reaction was slightly affected by allopurinol.

Key words: Biosensor, Xanthine oxidase, Inhibition