基于金属有机骨架的固定化氯过氧化物酶的制备和性能评价  

Immobilization of Chloroperoxidase in Metal Organic Framework and Its Catalytic Performance

作　　者：赵睿南 胡满成[1,2] 李淑妮[1,2] 翟全国[1,2] 蒋育澄[1,2] 

机构地区：[1]陕西师范大学化学化工学院,西安710119 [2]陕西师范大学大分子科学陕西省重点实验室,西安710119

出　　处：《化学学报》2017年第3期293-299,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(No.21176150)资助~~

摘　　要：30℃水相体系中"一锅法"快速制备固定化氯过氧化物酶(CPO@ZIF-8),在构筑金属有机沸石咪唑骨架结构(ZIF-8)的同时将氯过氧化物酶(CPO)固定在其三维纳米孔道中.温和的条件为固定化酶制备过程中酶活性的保持提供了前提.结构和性能表征说明酶分子的引入并不改变ZIF-8材料的孔道结构,同时酶分子在CPO@ZIF-8中呈现出在整体骨架材料中的嵌入式均匀分布.与先构筑ZIF-8骨架材料,然后通过表面吸附来固定酶分子的方法相比,通过将酶分子引入整体骨架材料中不仅提高了酶的固载量,更主要的是利用ZIF-8材料的高比表面积提高了固定化CPO的催化效率,同时基于三维孔道提供的刚性屏蔽环境有效改善了CPO在极端反应条件下的热稳定性、酸碱稳定性和对有机溶剂的耐受性.A rapid and efficient preparation of CPO@ZIF-8 by ＂one pot＂ method at 30 ℃ in aqueous solution is presented in this paper. The structure of zeolitic imidazolate frameworks （ZIF-8） was constructed while chloroperoxidase （CPO） was incorporated into the channel. Mild reaction conditions ensure maintaining the enzyme activity in the preparation of immobi- lized CPO. The synthesis of CPO@ZIF-8 was performed by mixing zinc nitrate solution and polyvinylpyrrolidone solution （PVP, Mw： 10000, 10 mg/mL, 400 p.L）, chloroperoxidase （CPO） （0.214 retool/L, 500 p.L） and 2-methylimidazole （1.25 mol/L, 25 mL） and stirring for 15 min at 30 ℃, followed by washing and centrifuging for 3 cycles at 4 ℃ for 8 min. The structure of CPO@ZIF-8 was characterized by scanning electron microscope （SEM）, transmission electron microscopy （TEM） and X-ray diffraction （XRD）, indicating that the incorporation of enzyme molecules did not affect the crystal structure of ZIF-8. To further confirm the incorporation of enzyme into ZIF-8, CPO was labeled by fluorescent probes fluorescein isothiocyanate （FITC） and subjected to the same procedure to synthesize the FITC-CPO@ZIF-8. Confocal laser scanning microscopy （CLSM） proved that CPO was distributed evenly and embedded in the whole framework of CPO@ZIF-8. Compared with the method of preparing ZIF-8 firstly, and then immobilizing enzyme molecule by physical adsorption, the immobilization effi- ciency of enzyme was enhanced by introducing the enzyme into the whole framework, moreover, the catalytic efficiency of the immobilized CPO was increased due to high specific surface area of ZIF-8. The catalytic performance of the CPO@ZIF-8 was evaluated by the conversion rate of 2,2＇-azinobis-（3-ethylbenzthiazoline-6-sulphonate） （ABTS）. The rigid shielding en- vironment provided by the three-dimensional channel of ZIF-8 effectively improved the thermal stability, pH stability, and tolerance to organic solvents of the CPO@ZIF-8 under harsh reaction c

关 键 词：氯过氧化物酶 金属有机框架 固定化酶 酶催化 稳定性 

分 类 号：Q814.2[生物学—生物工程] O627[理学—有机化学]