介孔TiO2固定化葡萄糖氧化酶的直接电化学性能

摘要

采用非模板软化学法制备了一种孔径均一的介孔TiO2材料(m-TiO2)。XRD测试结果表明其晶型为锐钛矿，且结晶度高，通过N2吸-脱附曲线可看出存在规整的介孔结构且具有高比表面，从FESEM和TEM可以看出制备的m-TiO2由许多纳米粒子构成微米级大颗粒，且存在均匀分布的介孔。将此种TiO2材料固定化葡萄糖氧化酶(GOx)后，通过红外光谱(FT-IR)分析可知m-TiO2材料可以有效固定化GOx。将m-TiO2作为固定化材料固定化GOx制备成Nafion/GOx/m-TiO2/GC电极并进行相关电化学测试，测试结果表明m-TiO2作为固定化材料固定化GOx后具有良好的催化活性，在无电子媒介体存在下能够实现反应电子与电极表面的直接电子传递，检测线性范围为0.1～1.2 mmol·L-1葡萄糖，灵敏度为3.44μA·mmol-1·L·cm-2，在葡萄糖传感领域具有良好的应用前景。%A novel mesoporous TiO2 material (m-TiO2) was obtained by a soft chemistry method in the absence of any surfactants or templates. It was shown that the m-TiO2 had an anatase crystalline structure with well-distributed mesopores from XRD, N2 adsorption-desorption isotherms, FESEM and TEM. The FT-IR results indicated that glucose oxidase (GOx) could be well immobilized on m-TiO2. The electrochemical tests of the fabricated Nafion/GOx/m-TiO2 modified glass carbon electrode (GCE) showed fast direct electron transfer between GOx molecules and electrode surface, exhibiting a linear response to glucose concentration ranging from 0.1 to 1.2 mmol·L-1, and good sensitivity of 3.44μA·mmol-1·L·cm-2, which proved that the novel m-TiO2 was a promising material for immobilization of GOx and fabrication of glucose biosensors.