Kinetic Behavior of Enzymes Immobilized Membranes in Potentiometric Biosensor: Homotopy Perturbation Method

Abstract

Organophosphorus Hydrolase (OPH) immobilized in a pH-based potentiometric biosensor exhibits non-steady-state behaviour, according to a theoretical model that has been discussed. The model represents the concentration of substrate and hydrolysis products within the membrane and is based on a system of five coupled nonlinear reaction-diffusion equations for enzyme reactions occurring in potentiometric biosensors under non-steady-state conditions.With the help of a novel application of the homotopy perturbation method, new approximate analytical expressions for the substrate concentration (organophosphorus pesticides, or OPs) and products are obtained for all values of the Thiele modulus and buffer concentration. A good agreement is found when the analytical and numerical results are compared. The results apply to the entire solution domain.