改良的YSI膜在葡萄糖传感器中的作用

为提高葡萄糖传感器的稳定性、检测精度、抗干扰能力及改善电极输出电流与葡萄糖浓度间的线性相关。在ＹＳＩ膜上固植过氧化氢酶，并在不同浓度的葡萄糖液、抗环血酸液和醋氨酚液中进行体外实验。结果显示：此传感器的背景电流为０．３７±０．０６ｎＡ；漂移值在０ｍＭＧ．Ｓ．中为（０．２０±０．１４）％／３ｈｒ，在１０ｍＭＧ．Ｓ．中为（３．２２±０．４０）％／３０ｈｒ，单位浓度单位时间的均值为０．１０３％；电极输出电流与葡萄糖浓度间的线性相关系数均值为０．９８６，线性范围为０～２０ｍＭＧ．Ｓ．；低浓度的抗坏血酸不能干扰传感器，高浓度的抗坏血酸和醋氨酚仅产生很小的干扰电流。因此，改良的ＹＳＩ酶膜使整个葡萄糖传感器系统性能、检测精度、抗干扰能力得到较明显的改善。

Function of Modified YSI Membrane in Glucose Semsor

This study was designed to improve the stability, accuracy and interference resistance of the glucose sensor system and to fomodify the correlation between electrode current and glucose concentration. Catalase was immobilized in YSI membrane. Experiments in vitro were conducted in different concentrations of glucose or ascorbic acid or paracetomol. The results showed the background current, 0.37 +/- 0.06 nA; the drift values in 0 mM G.S. and 10 mM G.S. were (0.20 +/- 0.14)%/30 hr and (3.22 +/- 0.40)%/30 hr respectively. The mean value of drift in 10 mM G.S. was 0.103% mM-1hr-1. The correlation between electrode current and glucose concentration gave satisfaction (r = 0.986); it ranged from 0 mM G.S. to 20 mM G.S. Lower concentration of ascorbic cid could not interfere n the glucose sensor system; higher concentration of ascorbic acid and paracetomol only produced very low interference current. These suggest that the modified YSI membrane contributes greatly to a stable, accurate and reliable glucose sensor system.