采用溶胶凝胶法合成二氧化硅覆盖的碳纳米管(CNTs/Si O2),通过化学键合法将CNTs/Si O2接上3-(甲基丙烯酰氧)丙基三甲氧基硅烷(MAPS),从而获得富含烯键的MAPS-CNTs/Si O2。以MAPS-CNTs/Si O2为分子印迹载体,芦丁为模板分子,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸酯为交联剂,自由基聚合法制备碳纳米管/二氧化硅的表面分子印迹聚合物(CNTs/Si O2-MIPs)。采用红外光谱、热重分析和扫描电镜等方法对CNTs/Si O2-MIPs进行表征,将CNTs/Si O2-MIPs滴涂至玻碳电极表面构建电化学传感器,采用循环伏安法和差分脉冲伏安法对CNTs/Si O2-MIPs修饰电极的电化学行为进行考察。结果表明,CNTs/Si O2-MIPs对芦丁具有良好的特异性吸附性能,印迹材料的DPV电流响应是非印迹材料的2.84倍;相对于其它类似的分子,如槲皮素、柚皮素、抗坏血酸,CNTs/Si O2-MIPs传感器对芦丁具有较好的选择性;CNTs/Si O2-MIPs传感器的电流响应与芦丁的浓度在0.1~100.0μmol/L范围内呈良好的线性关系,检出限(S/N=3)为0.032μmol/L。该传感器已成功应用于药片中芦丁含量的测定。
In this paper,Si O2-coated carbon nanotubes( CNTs / Si O2) were synthesized by sol- gel technique. The vinyl groups were introduced onto the surface of CNTs / Si O2 through chemical modification with γ-methacryloxypropyl trimethoxysilane( MAPS). Through free radical polymerization,CNTs / Si O2- MIPs were successfully obtained by the copolymerization in presence of MAPS- CNTs /Si O2 as support,rutin as template molecule,acrylamide as functional monomer and ethylene glycol dimethacrylate as crosslinker. CNTs / Si O2- MIPs were characterized by infrared spectrometry,thermal gravimetric analysis and scanning electronic microscopy. CNTs / Si O2- MIPs were coated onto glassy carbon electrode to construct an electrochemical sensor. The electrochemical characteristics of CNTs / Si O2- MIPs modified electrode were investigated by cyclic voltammetry and differential pulse voltammetry. The results showed that CNTs / Si O2- MIPs had a good specific adsorption property.DPV peak current response of CNTs / Si O2- MIPs sensor was nearly 2. 84 times that of the non-imprinted polymers. In addition, the CNTs / Si O2- MIPs sensor could recognize rutin from its relatively similar molecules of quercetin,naringenin and ascorbic acid. The CNTs / Si O2- MIPs sensor had a wide linear range over rutin concentration range of 0. 1- 100. 0 μmol / L with a detection limit( S / N =3) of 0. 032 μmol / L. The CNTs / Si O2- MIPs imprinted sensor was successfully used for the determination of rutin in tablets.