基于多壁碳纳米管和氧化锌纳米棒复合物的葡萄糖生物传感器(英文)

利用多壁碳纳米管(MWCNTs)和氧化锌(ZnO)纳米棒复合物膜构建了一种新的电流型葡萄糖生物传感器。MWCNTs-ZnO复合物在超声协助下通过静电配位的方式产生。其中,ZnO纳米棒的存在加强了该复合物催化氧化H2O2的能力,增加了响应电流。与单一的MWCNTs和ZnO相比,这种纳米复合物显示了更为有效地电催化活性。在此基础上,我们以MWCNTs-ZnO复合物膜为基底,用戊二醛交联法固定葡萄糖氧化酶,电聚合邻苯二胺(PoPD)膜为抗干扰层,构建了抗干扰能力强,稳定性好,灵敏度高,响应快的葡萄糖传感器。在+0.8V的检测电位下,该传感器对葡萄糖响应的线性范围为5.0×10-6~5.0×10-3mol·L-1(R=0.997),检测限为3.5×10-6mol·L-1(S/N=3),响应时间小于10s的葡萄糖生物传感器,常见干扰物质如抗坏血酸和尿酸不影响测定。

Glucose Biosensors Based on Nano-Composites of Multi-walled Carbon Nanotubes and Zinc Oxide Nanorods

We demonstrate herein a newly developed amperometric glucose biosensor by using multi-walled carbon nanotubes (MWCNTs) and zinc oxide (ZnO) nanorods composites film. The latter is generated by utilizing an electrostatic coordination approach under the assistance of the ultrasonic. The presence of ZnO nanorods in the composites enhances the abilities to electrocatalyze the oxidation of H₂O₂ and substantially raises the response current, which results in the composites exhibiting more efficiently electrocatalytic activity than those of MWCNTs and ZnO alone. As a result of the cross-linking reactions via glutaraldehyde, a layer of glucose oxidase (GOx) was firmly bound to the MWCNTs-ZnO film and an anti-interferent layer of poly(o-phenylenediamine) (PoPD) film was further electropolymerized on the enzyme film. At an applied potential of +0.8 V, the resulting biosensor performs a sensitive and selective electrochemical response to glucose in the presence of common interferences, such as ascorbic acid (AA) and uric acid (UA), with a linear dependence (R=0.997) on the glucose concentration in the range of 5.0×10^-6~5.0×10^-3 mol·L^-1 and a detection limit of 3.5×10^-6 mol·L^-1 at signal/noise=3. The response time was less than 10 s with addition of 5 mmol·L^-1 glucose. The MWCNTs-ZnO/GOx/PoPD modified glassy carbon electrode presents stable, high sensitivity and also exhibits fast amperometric response to the detection of glucose, which is promising for the development of glucose sensor.