MONOMOLECULAR ENZYME FILMS STABILIZED BY AMPHIPHILIC POLYELECTROLYTES FOR BIOSENSOR DEVICES

This paper describes the use of new amphiphilic polyelectrolytes for protein immobilization. Monomolecular films of glucose oxidase (GO) and monoamine oxidase (MAO) stabilized by amphiphilic polyelectrolytes (polyethyleneimine and poly-4-vinylpyridine derivatives modified by lauryl chains) were formed on a water surface in a Langmuir-Blodgett trough. The compressed films containing the enzymes were transferred onto the surface of a polypropylene membrane of a Clark electrode according to the Languir-Schaefer method. The analytical responses of the resulting biosensors were linear over the range 1-10 mM of glucose and 8-100 mu M of tyramine. Furthermore, direct functional coupling of GO and ferrocenecarboxylic acid in multilayer films stabilized by amphiphilic polyelectrolytes was demonstrated. The amperometric response of such a sensor was linear over the range 1-20 mM of glucose. The dependence of the kinetic parameters of the enzymes on the amphiphilic polyelectrolyte structures is discussed.