Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore.
Chemphyschem. 2013 Jul 22;14(10):2343-7. doi: 10.1002/cphc.201200961. Epub 2013 Jan 16.
Herein a novel strategy for the construction of an amperometric biosensor for highly sensitive and selective determination of glucose is described. The biosensor is made of a biocomposite membrane of glucose oxidase (GOx) and an Os(bpy)2 (bpy=2,2'-bipyridine)-based anionic redox polymer (Os-RP) mediator. The biosensor is fabricated through the co-immobilization of GOx and the Os-RP on the surface of a glassy carbon electrode by a simple one-step chemical crosslinking process. The crosslinked Os-RP/GOx composite membrane shows excellent catalytic activity toward the oxidation of glucose. Under optimal experimental conditions, a linear correlation between the oxidation current of glucose in amperometry at 0.25 V (vs. Ag/AgCl) and glucose concentration up to 10 mM with a sensitivity of 16.5 μA mM(-1) cm(-2) and a response time <5 s. Due to the presence of anionic sulfonic acid groups in the backbone of the redox polymer, the biosensor exhibits excellent selectivity to glucose in the presence of ascorbic acid and uric acid. The low hydrophobicity of the composite membrane also effectively retards the transport of molecular oxygen within the membrane.
本文描述了一种用于高灵敏度和选择性测定葡萄糖的电流型生物传感器的新构建策略。该生物传感器由葡萄糖氧化酶（GOx）和基于 Os(bpy)2（bpy=2,2'-联吡啶）的阴离子氧化还原聚合物（Os-RP）介体的生物复合膜制成。生物传感器通过将 GOx 和 Os-RP 通过简单的一步化学交联过程共固定在玻碳电极表面上而制造。交联的 Os-RP/GOx 复合膜对葡萄糖的氧化表现出优异的催化活性。在最佳实验条件下，在 0.25 V（相对于 Ag/AgCl）下进行安培法测定时，葡萄糖的氧化电流与葡萄糖浓度在 10 mM 以内呈线性相关，灵敏度为 16.5 μA mM(-1) cm(-2)，响应时间<5 s。由于氧化还原聚合物主链中存在阴离子磺酸基团，因此该生物传感器在存在抗坏血酸和尿酸的情况下对葡萄糖具有出色的选择性。复合膜的低疏水性还可以有效地阻止分子氧在膜内的传输。
