基于原位生长法制备纤维素气凝胶@ZIF-8复合材料及其对溶菌酶固定化的研究

Preparation of Cellulose Aerogel@ZIF-8 Composite by In-situ Growth Method and Its Immobilization for Lysozyme

中文关键词:  纤维素  气凝胶  原位生长  金属有机框架  固定化策略

Key Words:cellulose  aerogel  in-situ  metal-organic frameworks  immobilization strategy

中文摘要:

      随着生物化学和生命科学等领域的快速发展，酶工程成为研究热点；然而由于游离酶的结构敏感、易失活失效、且回收利用困难等，极大限制了它的发展和应用。通过吸附等手段将酶固定到特定载体中，可以提高酶活性和稳定性。本研究采用原位生长法制备结构规整的纤维素气凝胶@沸石咪唑酯骨架材料-8（ZIF-8）复合材料，并通过ZIF-8与蛋白之间的多重相互作用成功将溶菌酶固定；考察了pH值、盐浓度、吸附时间和吸附浓度对复合材料吸附性能及对固定化性能的影响。研究结果表明，纤维素气凝胶@ZIF-8对溶菌酶的最大固定化值为111.3 mg/g，并可在40 min内即可达到吸附平衡。催化实验研究结果发现，与游离酶相比，纤维素气凝胶@ZIF-8固定的溶菌酶具有更佳的催化效果。

Abstract:

      In recent years， with the rapid development of biochemistry and life sciences， the enzyme engineering has become a research hotspot. However， free enzymes have greatly limited its development and application due to its disadvantages such as sensitive structure， easy inactivation and failure， and difficulty in recycling. Immobilization of enzymes into specific carriers by means of adsorption or encapsulation can improve enzyme activity and stability， making further development possible. In this study， structurally regular cellulose aerogel@ZIF-8 composites were prepared using in situ growth method and lysozyme was successfully immobilized by multiple interactions between ZIF-8 and protein. Subsequently， the effects of pH value， NaCl concentration， adsorption time and adsorption concentration on the adsorption performance of the composites on the immobilization performance were investigated. The experimental results showed that the immobilization amount of cellulose aerogel@ZIF-8 lysozyme was 111.3 mg/g， the kinetics equilibrium can be completed within 40 minutes. In addition， the results of the catalytic experiments revealed that lysozyme immobilized by cellulose aerogel@ZIF-8 had better catalytic effect compared to the free enzyme. This study provides new ideas for the design and synthesis of sustainable and high performance immobilized materials.