多壁碳纳米管功能化及其在电化学葡萄糖传感器中的应用

摘要

利用硅烷偶联剂的表面修饰技术,将氨基丙基三乙氧基硅烷(APS)共价接枝到酸处理后的碳纳米管的表面.红外光谱数据证实了该反应的可行性.修饰后的碳纳米管在水中具有良好的分散性.利用西夫碱反应将氨基化的碳纳米管与醛基化的葡萄糖氧化酶共价层层自组装到电极表面,获得灵敏度可控的葡萄糖传感器.用电化学交流阻抗法和扫描电镜对成膜过程进行了跟踪,发现此膜的形成是一个逐步均匀的过程.与传统的葡萄糖传感器相比,该传感器制作简便,灵敏度高,且可以通过控制组装层数来调节该传感器的灵敏度与检测限.此外,该传感器具有相当好的稳定性及重现性.%Surface functionalization of multi-wall carbon nanotubes was carried out by acid treatment followed by reaction with multifunctional silane, 3-aminopropyltriethoxysilane.The chemical interaction of silane with the oxidized nanotube surface was confirmed by Fourier transform infrared spectroscopy (FT-IR).The resulting carbon nanotubes were uniformly dispersed in water.Such aminated nanotubos were utilized to fabricate glucose biosensor with periodate oxidized glucose oxidase through layer-by-layer covalent attachment on an aminated Au electrode.Electrochemical impedance spectroscopy and scanning electron micrographs followed the assembly process and verified that the films are formed in a progressive and uniform manner.The modified electrodes show excellent electrocatalytical response to the oxidation of glucose.From the analysis of voltammetric signal, the coverage of active enzyme on the electrode surface was estimated, which has a linear relationship with the number of deposited bilayers.This suggestes that the analytical performance such as sensitivity, detection limit, and so on, is tunable by controlling the number of the bilayer.In addition, the biosensor exhibited good reproducibility and stability.