LBL分子沉积法制备葡萄糖氧化酶电极

采用以静电力为主的逐层分子交替沉积技术制备葡萄糖氧化酶（GOD）电极.通过带有正电荷的聚二甲基二烯丙基铵盐酸盐（PDDA）和带有负电荷的GOD交替沉积在修饰有3-巯基-1-丙基磺酸钠（MPS）的金电极表面.以甲酸二茂铁为电子媒介体,用循环伏安法检测GOD电极对葡萄糖的响应.结果表明,当GOD电极组装层数小于4时,电流响应随着层数的增加而增大,超过4层时电流响应减小.其中4层GOD修饰电极的线性范围为0.55～6.63 mmol•L－1,当pH为7.0时,响应最大.同时电极的检测重现性能良好,相对标准偏差为2.4％.

Glucose Oxidase Modified Electrode Fabricated by Layer-by-layer Molecular Deposition

In this paper,glucose oxidase(GOD) electrodes were fabricated by alternative adsorption of oppositely charged polycations (poly(dimethydiallyammonium)hydrochloride, PDDA) and enzymes on Au modified by 3-mercapto-1-propanesulfonic acid, sodium salt (MPS). The concentration of glucose was detected by cyclic voltammetry via ferrocene monocarboxylic acid as mediator. A linear relationship existed between peak current and concentration of glucose in the range 0.55～6.63 mmol•L－1. The effect of pH on the response current of electroroxidation of glucose by GOD had been studied and the optimum pH was 7.0.In addition, the biosensor showed good reproducibility for the determination of glucose and the relative standard deviation was 2.4％.