Fabrication of polymer membranes with nanopores and a confinement effect toward enzyme immobilization has been an enabling endeavor. In the work reported here, an enzyme reactor based on a thermoresponsive magnetic porous block copolymer membrane was designed and constructed. Reversible addition–fragmentation chain transfer polymerization was used to synthesize the block copolymer, poly(maleic anhydride–styrene–N-isopropylacrylamide), with poly(N-isopropylacrylamide) as the thermoresponsive moiety. The self-assembly property of the block copolymer was used for preparation of magnetic porous thin film matrices with iron oxide nanoparticles. By covalent bonding of glutaminase onto the surface of the membrane matrices and changing the temperature to tune the nanopore size, we observed enhanced enzymolysis efficiency due to the confinement effect. The apparent Michaelis–Menten constant and the maximum rate of the enzyme reactor were determined (K_m = 32.3 mM, V_max = 33.3 mM min⁻¹) by a chiral ligand exchange capillary electrochromatography protocol with l-glutamine as the substrate. Compared with free glutaminase in solution, the proposed enzyme reactor exhibits higher enzymolysis efficiency, greater stability, and greater reusability. Furthermore, the enzyme reactor was applied for a glutaminase kinetics study. The tailored pore sizes and the thermoresponsive property of the block copolymer result in the designed porous membrane based enzyme reactor having great potential for high enzymolysis performance.

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具有纳米孔的聚合物膜的制造以及对酶固定化的限制作用一直是使人努力的努力。在本文报道的工作中，设计并构建了基于热响应性磁性多孔嵌段共聚物膜的酶反应器。可逆加成-断裂链转移聚合用于合成嵌段共聚物，聚（马来酸酐-苯乙烯-N-异丙基丙烯酰胺），与聚（N-异丙基丙烯酰胺）作为热敏部分。嵌段共聚物的自组装性质用于制备具有氧化铁纳米粒子的磁性多孔薄膜基质。通过将谷氨酰胺酶共价键合到膜基质表面并改变温度以调节纳米孔尺寸，我们观察到由于限制作用而提高了酶解效率。表观米氏常数和酶反应器的最大速率进行测定（ķ_米= 32.3毫米，V_最大= 33.3毫分钟^-1）通过与手性配体交换毛细管电协议升-谷氨酰胺为底物。与溶液中的游离谷氨酰胺酶相比，所提出的酶反应器具有更高的酶解效率，更高的稳定性和更高的可重复使用性。此外，该酶反应器用于谷氨酰胺酶动力学研究。嵌段共聚物的定制孔径和热响应性导致设计的基于多孔膜的酶反应器具有高酶解性能的巨大潜力。

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