Jung S K, Wilson G S
Department of Chemistry, University of Kansas, Lawrence 66045, USA.
Anal Chem. 1996 Feb 15;68(4):591-6. doi: 10.1021/ac950424p.
An oxidase-based glucose sensor has been developed that uses a mercaptosilane-modified platinum electrode to achieve selectivity of electrochemical interferants. A platinum-iridium (9:1) wire (0.178 mm o.d., sensing area of 1.12 mm2) is modified with (3-mercaptopropyl)trimethoxysilane. The modified sensors show excellent operational stability for more than 5 days. Glucose oxidase is immobilized on the modified surface (i) by using 3-maleimidopropionic acid as a linker or (ii) by cross-liking with bovine serum albumin using glutaraldehyde. Sensitivities in the range of 9.97 nA/mM glucose are observed when the enzyme is immobilized by method ii. Lower sensitivities (1.13 x 10(-1) nA/mM glucose) are observed when immobilization method i is employed. In terms of linear response range, the sensor enzyme-immobilized by method i is superior to that immobilized by method ii. The linearity is improved upon coating the enzyme layer with polyurethane. The sensor immobilized by method ii and coated with polyurethane exhibits a linear range to 15 mM glucose and excellent selectivity to glucose (0.47 nA/mM) against interferants such as ascorbic acid, uric acid, and acetaminophen.
一种基于氧化酶的葡萄糖传感器已被开发出来，它使用巯基硅烷修饰的铂电极来实现对电化学干扰物的选择性。一根铂铱（9:1）丝（外径0.178毫米，传感面积1.12平方毫米）用（3-巯基丙基）三甲氧基硅烷进行修饰。修饰后的传感器在超过5天的时间里表现出优异的操作稳定性。葡萄糖氧化酶通过以下两种方式固定在修饰表面：（i）使用3-马来酰亚胺丙酸作为连接剂；（ii）使用戊二醛与牛血清白蛋白交联。当通过方法ii固定酶时，观察到对葡萄糖的灵敏度在9.97纳安/毫摩尔葡萄糖范围内。当采用固定方法i时，观察到较低的灵敏度（1.13×10⁻¹纳安/毫摩尔葡萄糖）。就线性响应范围而言，通过方法i固定酶的传感器优于通过方法ii固定的传感器。在用聚氨酯涂覆酶层后，线性度得到改善。通过方法ii固定并涂覆聚氨酯的传感器对葡萄糖的线性范围达到15毫摩尔，并且对葡萄糖（0.47纳安/毫摩尔）相对于抗坏血酸、尿酸和对乙酰氨基酚等干扰物具有优异的选择性。
