Impact research of physical-chemical factors on the activity of modified enzyme electrodes

To modify graphite electrodes with a conductive enzyme polymer matrix, the method of drip application of a liquid polymer solution of various compositions was used: polyvinylpyrrolidone (40%), chitosan (0.1%), glutaric dialdehyde (0.1%), glucoxidase and peroxidase in a ratio of 2:5. To assess the effect of the immobilization time (x1), the pH of immobilization (x2) and the enzyme/carrier ratio (x3) on the activity of the enzyme electrodes, a three-factor and three-level Box-Benken and RSM design was used. This model was able to adequately predict the results of immobilization within the range of variables used. The most favorable conditions and the largest number of molecules of the enzyme complex are in the electrochemically active state when they are immobilized on PVP using modifying agents chitosan and glutaraldehyde. The results demonstrate that the productivity of the enzymatic biofuel element is directly proportional to the activity of the immobilized GOX/HRP complex, since in this case the glucose oxidation reaction can proceed more efficiently.