Department of Applied Physics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
Biosens Bioelectron. 2010 Mar 15;25(7):1646-51. doi: 10.1016/j.bios.2009.11.027. Epub 2009 Dec 16.
Pt electrodes have been modified with electrospun titanium dioxide (TiO(2)) nanofibers with controllable densities for electrochemical detection. The TiO(2) nanofiber/Pt electrodes show excellent electrocatalytic activity to electro-oxidation of hydrogen peroxide and the response current density to an addition of hydrogen peroxide is 30% higher than that for a Pt electrode. Glucose oxidase (GOx) molecules have been effectively immobilized on the surface of the TiO(2) nanofibers and the resulted chitosan/GOx/TiO(2) nanofiber/Pt electrodes with a optimum density of nanofibers exhibit excellent glucose bioelectrocatalytic performance including good amperometric current response (9.25 microA cm(-2)mM(-1)), short response time (10s) and low detection limit (0.01 mM). We have found that the nanofibers modified on the Pt electrode improved the sensitivity of the enzyme electrode to glucose for 2.7 times and extended the detection limit by one order of magnitude in comparison with flat Pt electrodes. It is expected that electrodes modified with electrospun TiO(2) nanofibers will find more promising applications in high performance electrochemical biosensors.
铂电极已通过静电纺丝技术进行修饰，将具有可控密度的二氧化钛（TiO2）纳米纤维附着其上，用于电化学检测。TiO2 纳米纤维/铂电极对过氧化氢的电化学氧化具有优异的电催化活性，添加过氧化氢后的响应电流密度比铂电极高 30%。葡萄糖氧化酶（GOx）分子已被有效固定在 TiO2 纳米纤维的表面上，所得的壳聚糖/GOx/TiO2 纳米纤维/铂电极在具有最佳纳米纤维密度的情况下，表现出优异的葡萄糖生物电化学催化性能，包括良好的安培电流响应（9.25 μA cm-2mM-1）、较短的响应时间（10s）和较低的检测限（0.01 mM）。我们发现，与平面铂电极相比，修饰在铂电极上的纳米纤维将酶电极对葡萄糖的灵敏度提高了 2.7 倍，并将检测限提高了一个数量级。预计修饰有静电纺丝 TiO2 纳米纤维的电极将在高性能电化学生物传感器中得到更广泛的应用。
