A description of the implementation of the relaxation method with automatic mesh point allocation for. immobilized enzyme electrodes is presented. The advantages of this method for the solution of coupled reaction-diffusion problems are discussed. The relaxation numerical simulation technique is combined with the Simplex fitting algorithm to extract kinetic parameters from experimental data. The results of the simulations are compared to experimental data from self-assembled multilayered electrodes comprised of glucose oxidase (GOx) and an Os modified redox mediator and found to be in excellent agreement. (c) 2008 Elsevier B.V. All rights reserved.