Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore.
ACS Appl Mater Interfaces. 2010 Nov;2(11):3083-91. doi: 10.1021/am100591t. Epub 2010 Oct 22.
An amperometric glucose biosensor was prepared using polyaniline (PANI) and chitosan-coupled carbon nanotubes (CS-CNTs) as the signal amplifiers and glucose oxidase (GOD) as the glucose detector on a gold electrode (the Au-g-PANI-c-(CS-CNTs)-GOD biosensor). The PANI layer was prepared via oxidative graft polymerization of aniline from the gold electrode surface premodified by self-assembled monolayer of 4-aminothiophenol. CS-CNTs were covalently coupled to the PANI-modified gold substrate using glutaradehyde as a bifunctional linker. GOD was then covalently bonded to the pendant hydroxyl groups of chitosan using 1,4-carbonyldiimidazole as the bifunctional linker. The surface functionalization processes were ascertained by X-ray photoelectron spectroscopy (XPS) analyses. The field emission scanning electron microscopy (FESEM) images of the Au-g-PANI-c-(CS-CNTs) electrode revealed the formation of a three-dimensional surface network structure. The electrode could thus provide a more spatially biocompatible microenvironment to enhance the amount and biocatalytic activity of the immobilized enzyme and to better mediate the electron transfer. The resulting Au-g-PANI-c-(CS-CNTs)-GOD biosensor exhibited a linear response to glucose in the concentration range of 1-20 mM, good sensitivity (21 μA/(mM·cm(2))), good reproducibility, and retention of >80% of the initial response current after 2 months of storage.
一种安培型葡萄糖生物传感器，是使用聚苯胺（PANI）和壳聚糖偶联碳纳米管（CS-CNTs）作为信号放大器，葡萄糖氧化酶（GOD）作为葡萄糖探测器，在金电极上制备而成（Au-g-PANI-c-（CS-CNTs）-GOD 生物传感器）。PANI 层是通过自组装的 4-巯基苯胺单层预修饰的金电极表面上苯胺的氧化接枝聚合制备的。CS-CNTs 通过戊二醛作为双功能连接物共价偶联到 PANI 修饰的金基底上。然后，GOD 通过 1,4-碳二亚胺作为双功能连接物共价键合到壳聚糖的侧基羟基上。表面功能化过程通过 X 射线光电子能谱（XPS）分析来确定。Au-g-PANI-c-（CS-CNTs）电极的场发射扫描电子显微镜（FESEM）图像显示出三维表面网络结构的形成。因此，该电极可以提供更具空间生物相容性的微环境，以增加固定化酶的数量和生物催化活性，并更好地介导电子转移。所得的 Au-g-PANI-c-（CS-CNTs）-GOD 生物传感器对 1-20 mM 浓度范围内的葡萄糖表现出线性响应，具有良好的灵敏度（21 μA/（mM·cm2））、良好的重现性和在 2 个月的储存后保留超过 80%的初始响应电流。
