REGULATORY ROLE OF SURFACTANTS IN THE KINETICS OF GLUCOSE OXIDASE-CATALYZED OXIDATION OF D-GLUCOSE BY FERROCENIUM AND N-BUTYLFERROCENIUM IONS

The effect of micelles of different surfactants (cationic, anionic, an d neutral) on the kinetics of the glucose oxidase-catalyzed reduction of ferrocenium cations RFc(+) (R = H, Bu-n) by D-glucose was studied b y spectrophotometry. In micellar media of Triton X-100 and sodium dode cyl sulfate (SDS), the Michaelis dependence of the reaction rate on th e HFc(+) concentration is observed, while this dependence has an extre me character in cationic micelles of cetyltrimethylammonium bromide (C TAB). The nature and concentration of surfactants of all types have a slight effect an the rate of reduction of HFc(+). The level of enzymat ic activity is approximately equal in the case of Triton X-100 and CTA B and is considerably lower in the SDS micelles. On going from HFc(+) to Bu(n)Fc(+), the reaction rate is maximum in the cationic CTAB micel les, the anionic SDS micelles exhibit almost no activity, and the acti vity has an intermediate value in neutral micelles of Triton X-100. Th e conditions are presented under which the micellar medium controls th e catalytic activity of glucose oxidase with respect to ferrocenium ca tions.