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将葡萄糖氧化酶和高氯酸二茂铁同时固定在微盘铂电极表面上的含Nafion的聚电解质内,成功地研制出微型化的葡萄糖传感器,获得了各种优化的实验条件:如稀释Nafion的水溶液中葡萄糖氧化酶的相对浓度、高氯酸二茂铁的浓度以及氧气等对葡萄糖测定的影响。高氯酸二茂铁对过氧化氢具有电催化氧化作用,酶基反应生成的过氧化氢能够在电极表面上用安培法检测。另外,在无氧条件下,高氯酸二茂铁本身也可单独作为葡萄糖氧化酶的电子媒体从而保证该修饰电极的酶循环。Nafion膜具有阳离子交换性能,抗坏血酸在电极上表现出较小的干扰,同时,由于检测电位较低,象尿酸这类需要在较高电位下才能检测的电活性物质在此修饰电极上也无干扰,在无氧条件下,根据Michaehs-Menten方程分析:当C_(Fe)=1.0mmol/L,Miehaelis常数为10.7mmol/L。最大极限电流为5.1nA;当C_(Fe)=2.0mmol/L,Michaelis常数和最大极限电流分别为7.06mmol/L和5.8nA。而且该修饰电极显示了较好的电极稳定性。
Glucose oxidase and ferrochloric perchlorate were simultaneously immobilized in the Nafion-containing polyelectrolyte on the surface of the microdisk platinum electrode. The miniaturized glucose sensor was successfully developed and various optimized experimental conditions were obtained. For example, dilute Nafion The relative concentration of glucose oxidase in aqueous solution, the concentration of ferrochloric perchlorate and the effect of oxygen on the determination of glucose. Ferrochloric perchlorate has electrocatalytic oxidation of hydrogen peroxide, and hydrogen peroxide generated by enzymatic reaction can be detected by amperometry on the electrode surface. In addition, under anaerobic conditions, ferrochloric perchlorate alone can also serve as an electronic medium for glucose oxidase to ensure that the modified electrode enzyme cycle. Nafion membranes have cation exchange properties with ascorbic acid showing less interference at the electrode and, at the same time, electroactive substances like uric acid, which can be detected at higher potentials, have no interference at this modified electrode due to lower detection potentials Under anaerobic conditions, according to the Michaehs-Menten equation analysis: when Fe (Fe) = 1.0mmol / L, Miehaelis constant is 10.7mmol / L. The maximum current limit is 5.1nA. The Michaelis constant and the maximum current limit are 7.06mmol / L and 5.8nA respectively when C_ (Fe) = 2.0mmol / L. Moreover, the modified electrode shows better electrode stability.