LAYER BY LAYER DEPOSITION OF REDOX POLYMERS/ENZYME ASSEMBLIES ONTO ELECTRODES SURFACES FOR NITRATE ELECTROCHEMICAL SENSING

摘要

Gold electrodes were used as supports for the layer-by-layer deposition of nitrate reductase (NR) and oppositely charged polyviologen derivative (PV) to prepare high-surface area thin films for electroanalysis. Formation of the multilayer films was verified by cyclic voltammetry (CV). The activity of the NR/PV multilayer films was found to be dependent on the amounts of enzyme and mediator in the film, which is determined by the number of enzyme/mediator layers deposited. Films containing NR/PV assemblies showed regularly increasing bioactivity up to eight enzyme/mediator bilayers, with a plateau in activity observed thereafter. This reported method provides a viable approach for the preparation of high-enzyme-content thin films with tailored bioactivity.