Kinetic model of pH-based potentiometric enzymic sensors. Part 3. Experimental verification

Abstract

An experimental verification of the kinetic model for a pH-based potentiometric enzymic sensor is presented. For this purpose the experimental results obtained using a urea sensor prepared by the immobilization of urease on the hydrogen ion sensitive surface of a glass electrode were employed. The effects of buffer capacity and pH and also the rate of solution stirring on the electrode response were examined and the results obtained were compared with those predicted theoretically. The influence of local changes in pH within the enzymic layer of the sensor on the enzyme kinetics is also discussed.