Fang Aiping, Ng Hou Tee, Li Sam Fong Yau
Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
Biosens Bioelectron. 2003 Oct 30;19(1):43-9. doi: 10.1016/s0956-5663(03)00133-7.
In this paper, a mediatorless amperometric glucose biosensor based on direct covalent immobilisation of monomolecular layer of glucose oxidase (GOx) on a semiconducting indium-tin oxide (ITO) is demonstrated. The abundance of surface hydroxyl functional group of ITO allows it to be used as a suitable platform for direct covalent immobilisation of the enzyme for sensor architecture. The anodic current corresponding to electrochemical oxidation of the enzymatic product, hydrogen peroxide, at a sputtered Pt electrode at 0.500 V (vs. SCE) was obtained as the sensor signal. It was found that the biosensor based on the direct immobilisation scheme shows a fast biosensor response, minimum interference from other common metabolic species and ease of biosensor miniaturisation. A linear range of 0-10 mM of glucose was demonstrated, which exhibits a high sensitivity as far as performance per immobilised GOx molecule is concerned. A detection limit as low as 0.05 mM and long-term stability were observed. Even more important, the biosensor design allows fabrication through a dry process. These characteristics make it possible to achieve mass production of biosensor compatible with the current electronic integrated circuit manufacturing technologies.
本文展示了一种基于葡萄糖氧化酶（GOx）单分子层直接共价固定在半导体氧化铟锡（ITO）上的无 mediator 电流型葡萄糖生物传感器。ITO 表面丰富的羟基官能团使其能够用作直接共价固定酶以构建传感器结构的合适平台。在溅射的 Pt 电极上于 0.500 V（相对于 SCE）获得对应于酶促产物过氧化氢电化学氧化的阳极电流作为传感器信号。发现基于直接固定方案的生物传感器显示出快速的生物传感器响应、来自其他常见代谢物的最小干扰以及生物传感器小型化的便利性。展示了 0 - 10 mM 葡萄糖的线性范围，就每个固定的 GOx 分子的性能而言，该范围具有高灵敏度。观察到检测限低至 0.05 mM 以及长期稳定性。更重要的是，该生物传感器设计允许通过干法制造。这些特性使得能够实现与当前电子集成电路制造技术兼容的生物传感器的大规模生产。
