基于碳纳米管无纺布的葡萄糖氧化酶生物传感器

Glucose oxidase biosensors based on carbon nanotube non-woven fabrics

以化学气相沉积法直接合成的碳纳米管无纺布作为电极材料,采用简单的包埋法,通过葡萄糖氧化酶和聚乙烯醇的水溶液固定葡萄糖氧化酶制备生物传感器。利用SEM、TEM和BET表征碳纳米管无纺布的内部形貌及孔径分布;利用双电测四探针测试仪和万用表测定碳纳米管无纺布的导电性能;利用拉伸仪测试碳纳米管无纺布的力学性能;利用电化学工作站测定生物传感器的电化学行为及电流响应信号。结果显示传感器的响应电流随葡萄糖浓度的增加呈线性变化,线性范围为2.5 mmol/L^30 mmol/L,检出限为2.5 mmol/L,响应时间约10 s,经硝酸处理可进一步提高传感器的响应电流。基于碳纳米管无纺布的葡萄糖氧化酶生物传感器可实现对葡萄糖的有效检测。

Glucose oxidase biosensors were fabricated by vacuum-impregnation of a glucose oxidase in a polyvinyl alcohol （PVA） aqueous solution into carbon nanotube non-woven fabrics （CNTFs）.The performance of the biosensor was evaluated by an electrochemical method,using the biosensors as working electrode,Pt wire as a counter electrode and Ag/AgCl as a reference electrode.The electrical conductivity of the CNTFs was tested with a four-probe method.Tensile strength was measured by a tensile tester.Results show that the response currents of the biosensors increase linearly with the glucose content in aqueous solutions.The linear range is from 2.5 to 30 mmol/L,the detection limit is 2.5 mmol/L and the response time is about 10 s.An acid treatment of the CNTF with 65 ％ HNO3 can increase the response current.