Zhang Yanmei, Li Jun, Han Difei, Zhang Huidong, Liu Peng, Li Can
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, P.O. Box 110, Dalian 116023, China.
Biochem Biophys Res Commun. 2008 Jan 25;365(4):609-13. doi: 10.1016/j.bbrc.2007.10.205. Epub 2007 Nov 20.
The combination of magnetic nanoparticles and mesoporous silica can present a strategy for enzyme immobilization. In this work, magnetic siliceous mesocellular foam functionalized with octyl groups was prepared and used as support for lipase adsorption. Almost all the active lipases in crude enzyme solution were adsorbed by this magnetically separable, hydrophobic siliceous mesocellular foam. The resolution of 1-phenylethanol acylated with vinyl acetate can be achieved in 1.5h using the resultant magnetic biocatalyst, whereas only 30% conversion was obtained by using the free lipase under the identical reaction conditions. These results are probably due to the "interfacial adsorption" and "hyper-activation" of lipase on the hydrophobic surface of the magnetic siliceous mesocellular foam. Moreover, the biocatalyst entrapped in the nanopores of this foam can be recycled magnetically for at least seven times without significant loss of its activity and enantioselectivity.
磁性纳米颗粒与介孔二氧化硅的结合可为酶固定化提供一种策略。在本工作中，制备了用辛基官能化的磁性硅质介孔泡沫，并将其用作脂肪酶吸附的载体。粗酶溶液中几乎所有的活性脂肪酶都被这种可磁分离的疏水性硅质介孔泡沫吸附。使用所得的磁性生物催化剂，在1.5小时内可实现用乙酸乙烯酯酰化的1-苯乙醇的拆分，而在相同反应条件下使用游离脂肪酶仅获得30%的转化率。这些结果可能归因于脂肪酶在磁性硅质介孔泡沫疏水表面上的“界面吸附”和“超活化”。此外，截留在这种泡沫纳米孔中的生物催化剂可通过磁性回收至少七次，而其活性和对映选择性不会有明显损失。
