聚邻苯二胺膜电极中辣根过氧化物酶的电子传递
Electron TransFer of Horseradish Peroxidase Entrapped in Poly-o-phenylenediamine Membrane Electrode
Abstract
利用酶的电化学固定化方法制备合辣根过氧化物酶的聚邻苯二胺膜电极,研究其伏安行为及对H2O2还原的生物电催化作用.结果表明,在所述生物电催化反应中酶与聚合物基质发生了直接电子传递.但对新制的酶电极而言,电聚合时生成并包理在酶膜中的寡聚体可作为电子传递体加速氧化态酶的再生.根据酶电极电流响应实验曲线的拟合,发现氧化态酶的再生速度随电极电位的变化表观上符合TAfEl关系式.提出了酶反应动力学参数的测定方法. The poly-o-phenylenediamine membrane electrode containing horseradish peroxi-dase was prepared by means of the electrochemical immobilization of enzyme, and thevoltammetric behavior of the resulting enzyme electrode and its bioelectrocatalysis to hydro-gen peroxide reduction was studied.It was Found that the direct electron tansFer between theenzyme and the polymer matrix takes place in the biocatalytic processes.For the newly pre-pared enzyme electrode, however, the oligomers, which are Formed during the polymeriza-tion of o-phenylenediamine and then incorporated in the enzyme membrane, can play a role ofelectron transFer mediators to accelerate the regeneration of the oxidized enzyme.From theFitting of experimental current response curves, it can be Found that the change in the regen-eration rates of the oxidized enzyme with the electrode potentials obeys apparantly the TaFelrelationship.The procedure in the measurement of kinetic parameters For enzyme reactionswas suggested.