铁氨基黏土-葡萄糖氧化酶纳米复合催化剂的构筑及多酶级联反应研究

以铁氨基黏土(FeAC)为载体, 通过共价交联固定葡萄糖氧化酶(GO_x), 构筑了铁氨基黏土-葡萄糖氧化酶纳米复合催化剂(FeAC-GO_x). 利用FeAC的过氧化物酶活性, 与GO_x结合进行级联反应, 可催化葡萄糖转化为过氧化氢并产生显色反应; 采用扫描电子显微镜(SEM)、 X射线衍射(XRD)和傅里叶变换红外光谱(FTIR)对FeAC-GO_x进行了形貌和结构表征, 并评价了其酶动力学参数、 催化稳定性和重复使用性等. 结果表明, GO_x的固定化率可达到76.4%, 所构筑的纳米结构酶复合体系具有高效的级联催化能力. 与天然酶体系相比, FeAC-GO_x具有更优异的温度和pH耐受性, 且在重复使用6次后, 酶催化活性无明显降低. 该体系不仅为新型葡萄糖传感器的开发奠定了基础, 还为多酶级联纳米结构酶的构筑提供了新思路.

Construction of Fe-aminoclay-glucose Oxidase Nanocomposite Catalyst and Its Multi-enzyme Cascade Analysis

Glucose oxidase（GO_x） and Fe-aminoclay（FeAC） were combined to construct a mimic multi- enzyme system（FeAC-GO_x） for cascade reaction. FeAC exhibit peroxidase-like activity which can catalyze H₂O₂ generated by GOx and trigger color reaction. The obtained FeAC-GO_x was characterized by scanning electron microscope（SEM）， X-ray diffraction（XRD）， and fourier transform infrared spectroscopy（FTIR）. The enzymatic kinetics， catalytic stability and reusability were evaluated. As a result， the immobilization efficiency of GO_x could reach to 76.4%， and FeAC-GO_x exhibited excellent cascade catalysis activity. Compared with the free enzyme， FeAC not only possessed a strong tolerance toward temperature and pH， but also presented excellent reusability. The catalytic activity of reused FeAC barely changed after six repetitions. This strategy may lay the foundation to the development of a new glucose biosensor， and provide a novel approach to design multi-enzyme cascade system.