Wu Bao-Yan, Hou Shi-Hua, Yin Feng, Li Jing, Zhao Zi-Xia, Huang Jia-Dong, Chen Qiang
The key Laboratory of Bioactive Materials Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China.
Biosens Bioelectron. 2007 Jan 15;22(6):838-44. doi: 10.1016/j.bios.2006.03.009. Epub 2006 May 3.
A new strategy for fabricating glucose biosensor was presented by layer-by-layer assembled chitosan (CS)/gold nanoparticles (GNp)/glucose oxidase (GOD) multilayer films modified Pt electrode. First, a cleaned Pt electrode was immersed in poly(allylamine) (PAA), and then transferred to GNp, followed by the adsorption of GOD (GOD/GNp/PAA/Pt). Second, the GOD/GNp/PAA/Pt electrode was immersed in CS, and then transferred to GNp, followed by the adsorption of GOD (GOD/GNp/CS/GOD/GNp/PAA/Pt). Third, different layers of multilayer films modified Pt electrodes were assembled by repeating the second process. Film assembling and characterization were studied by quart crystal microbalance, and properties of the resulting glucose biosensors were measured by electrochemical measurements. The results confirmed that the assembling process of multilayer films was simple to operate, the immobilized GOD displayed an excellent catalytic property to glucose, and GNp in the biosensing interface efficiently improved the electron transfer between analyte and electrode surface. The amperometric response of the biosensors uniformly increased from one to six layers of multilayer films, and then reached saturation after the seven layers. Among the resulting biosensors, the biosensor based on the six layers of multilayer films was best. It showed a wide linear range of 0.5-16 mM, with a detection limit of 7.0 microM estimated at a signal-to-noise ratio of 3, fast response time (within 8s). Moreover, it exhibited good reproducibility, long-term stability and interference free. This method can be used for constructing other thin films, which is a universal immobilization method for biosensor fabrication.
通过层层组装壳聚糖（CS）/金纳米颗粒（GNp）/葡萄糖氧化酶（GOD）多层膜修饰铂电极，提出了一种制备葡萄糖生物传感器的新策略。首先，将清洁后的铂电极浸入聚烯丙胺（PAA）中，然后转移至GNp中，接着吸附GOD（GOD/GNp/PAA/Pt）。其次，将GOD/GNp/PAA/Pt电极浸入CS中，然后转移至GNp中，接着吸附GOD（GOD/GNp/CS/GOD/GNp/PAA/Pt）。第三，通过重复第二步过程组装不同层数的多层膜修饰铂电极。利用石英晶体微天平研究膜的组装和表征，并通过电化学测量来测定所得葡萄糖生物传感器的性能。结果证实，多层膜的组装过程操作简单，固定化的GOD对葡萄糖表现出优异的催化性能，且生物传感界面中的GNp有效地改善了分析物与电极表面之间的电子转移。生物传感器的安培响应随着多层膜层数从一层增加到六层而均匀增加，在七层后达到饱和。在所得的生物传感器中，基于六层多层膜的生物传感器性能最佳。它显示出0.5 - 16 mM的宽线性范围，在信噪比为3时估计检测限为7.0 microM，响应时间快（8秒内）。此外，它具有良好的重现性、长期稳定性且无干扰。该方法可用于构建其他薄膜，是一种用于生物传感器制造的通用固定化方法。
