Glucose oxidase (GOD) was immobilized in four different conducting polymer matrices, namely: polyprrole, (PPy), poly(pyrrole-graft-polytetrahydrofuran). (1) and (3): and poly(pyrrole-graft-polystyrene polytetrahydrofuran), (2). The kinetic parameters V-max and K-m, and the optimum temperature were determined for both immobilized and native enzymes. The effect of electrolysis time and several supporting electrolytes. p-toluenesulfonic acid, p-toluene sulfonic acid (PTSA), sodium p-toluene sulfonate. Sodium p-toluene sulfonate (NaPTS). and sodium dodecyl sulfate. sodium dodecyl sulfate (SDS), on enzyme immobilization were investigated. The high K-m value (59.9 mM) of enzyme immobilized in PPy was decreased aria immobilization in graft copolymer matrices of pyrrole, V-max, which was 2.25 mM/min for pure PPy, as found as 4.71 mM/min for compound (3). (C) 2002 Elsevier Science B.V. All rights reserved.