Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
J Mater Chem B. 2023 Jul 12;11(27):6428-6434. doi: 10.1039/d3tb00844d.
Enzyme immobilization is a suitable strategy to promote biosensing, biocatalysis and the industrial applications of biomacromolecules. Although considerable efforts have been devoted to the construction of metal-organic frameworks (MOFs)-based porous nano-reactors, their enzymolysis efficiency cannot be tuned by varying the external conditions due to the fixed conformation of the encapsulated enzymes. In this work, a controllable embedding protocol was developed based on the concept of stimuli-responsive polymer modified MOFs. Using MOFs as a rigid template for thermo-responsive polymer modification and consequently utilizing the polymer-MOFs complexes for enzyme (glucose oxidase, horseradish peroxidase, trypsin, cytochrome , glutaminase) immobilization, different porous nano-reactors were fabricated. Most importantly, the polymer on the MOF surface exhibited good ability to form a "soft nest" at high temperature for inducing the confinement effect and further improving the enzymolysis efficiencies of the nano-reactors 3.75-37.7-fold. Moreover, a colorimetric sensing method was developed to detect serum glucose with the proposed nano-reactors. This strategy is highly versatile and suitable for diverse rigid MOFs modified with stimuli-responsive soft-polymer-nests and enzymes.
酶固定化是促进生物传感、生物催化和生物大分子工业应用的一种合适策略。尽管已经投入了相当大的努力来构建基于金属有机框架（MOFs）的多孔纳米反应器，但由于包封酶的固定构象，它们的酶解效率不能通过改变外部条件来调节。在这项工作中，基于刺激响应聚合物修饰的 MOFs 的概念，开发了一种可控的嵌入方案。使用 MOFs 作为热响应聚合物修饰的刚性模板，并利用聚合物-MOFs 配合物进行酶（葡萄糖氧化酶、辣根过氧化物酶、胰蛋白酶、细胞色素 C、谷氨酰胺酶）固定化，制备了不同的多孔纳米反应器。最重要的是，MOF 表面的聚合物在高温下具有良好的形成“软巢”的能力，从而诱导限域效应，进一步将纳米反应器的酶解效率提高了 3.75-37.7 倍。此外，还开发了一种比色传感方法，利用所提出的纳米反应器检测血清葡萄糖。该策略具有高度通用性，适用于各种经过刺激响应软聚合物巢和酶修饰的刚性 MOFs。
