Mathematical model for analysis of oxidoreductase enzyme kinetics in an amperometric biosensor

Abstract

A non-linear mathematical model is proposed and analysed to study the effect of different parameters on the performance of amperometric biosensor. The model is based on non-linear reaction-diffusion containing non-linear term related to Michaelis-Menten enzyme reaction system. In modelling the device, approximate analytical solutions for the non-linear equations under steady-state conditions by using the Adomian Decomposition Method (ADM) are obtained. Simple and approximate polynomial expressions for the concentration of substrate, product and current response are reported in terms of Thiele moduli, saturation parameters and the normalized surface concentrations of species. Furthermore, the numerical simulations of the problem are performed by applying finite difference method by using Matlab software to reaction-diffusion equation as a function of time and space. By changing model parameters, the output results are numerically analysed at steady state conditions. The limiting cases of catalytic site saturation and unsaturated site are considered and analysis for dependence of substrate, product and current response on diffusion moduli, enzyme thickness and saturation parameter is reported. The provided analytical solution is simple and more efficient to understand the behaviour of the amperometric biosensor system.