Y. Kobayashi et J. Anzai, Preparation and optimization of bienzyme multilayer films using lectin andglyco-enzymes for biosensor applications, J ELEC CHEM, 507(1-2), 2001, pp. 250-255
Enzyme multilayer films were prepared on the surface of a glassy carbon ele
ctrode by a layer-by-layer deposition of concanavalin A (Con A) and horsera
dish peroxidase (HRP) or glucose oxidase (GOx) alternately. The enzyme thin
films were formed through biological affinity between Con A and sugar chai
ns intrinsically located on the surface of the enzymes. Both HRP and GOx re
tained their catalytic activity in the multilayer film and the enzyme-modif
ied electrodes served as enzyme biosensors. For the glucose sensors prepare
d using HRP-GOx bienzyme multilayer films, the loading and geometry of the
enzymes in the multilayer film were optimized by varying the number of enzy
me layers and the sequence of immobilization in the multilayer film. The ma
gnitude of response of the glucose sensors increased with the increasing nu
mber of Cox layers, while the bilayers of HRP sufficed for attaining maximu
m response. It was found that the electrode surface should be first coated
with HRP layers and then the GOx layer should be immobilized as an outer la
yer to obtain higher performance sensors. The results were explained reason
ably based on the relative activity of the enzymes and the reaction scheme.
(C) 2001 Elsevier Science B.V. All rights reserved.