Sakai Jin, Sasaki Kohki, Nakatani Riki, Das Saikat, Negishi Yuichi
Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
Research Institute for Science & Technology, Tokyo University of Science, Tokyo 162-8601, Japan.
Nanoscale. 2024 Dec 5;16(47):21767-21775. doi: 10.1039/d4nr02506g.
Silver cluster-assembled materials (SCAMs) epitomize well-defined extended crystalline frameworks that combine the ingenious designability at the atomic/molecular level and high structural robustness. They have captivated the interest of the scientific fraternity because of their modular construction which enables to systematically tailor their functions, and their capacity to not only inherit the characteristics of component building units but also introduce their uniqueness in endowing the final material with extraordinary properties. Herein, we demonstrate the synthesis of a novel (3,6)-connected two-dimensional (2D) SCAM [Ag(SBu)(CFCOO)(THIT)] (described as TUS 5, THIT = 2,4,6-tri(1-imidazol-1-yl)-1,3,5-triazine) composed of Ag cluster nodes and tritopic imidazolyl linkers. We have leveraged, for the first time, this precisely architected extended SCAM structure as a support matrix for enzyme immobilization. The electrostatic attraction between the negatively charged amano lipase PS and positively charged TUS 5 as well as the surface hydrophobicity of TUS 5 catered to great binding of lipase onto the TUS 5 matrix, in addition to boosting the activity of lipase interfacial activation. Capitalizing on the cooperative benefits of organic and inorganic support matrices wherein organic supports impart with cost-efficiency, biocompatibility, and improved enzyme stability and reusability and inorganic supports confer high thermal, mechanical and microbial resistance, we have utilized the immobilized lipase on TUS 5 SCAM (lipase@TUS 5) for the kinetic resolution of (,)-1-phenylethanol by transesterification reaction. Importantly, lipase@TUS 5 could attain appreciably higher conversion into ()-1-phenylethyl acetate, besides featuring superior thermal stability, solvent tolerance and recyclability, over the native lipase.
银簇组装材料（SCAMs）是定义明确的扩展晶体框架的典范，它结合了原子/分子水平上巧妙的可设计性和高结构稳健性。由于其模块化结构能够系统地调整其功能，以及它们不仅能够继承组成构建单元的特性，还能在赋予最终材料非凡性能方面引入其独特性，因此吸引了科学界的关注。在此，我们展示了一种新型的（3,6）连接二维（2D）SCAM [Ag(SBu)(CFCOO)(THIT)]（称为TUS 5，THIT = 2,4,6-三（1-咪唑-1-基）-1,3,5-三嗪）的合成，该材料由银簇节点和三齿咪唑基连接体组成。我们首次利用这种精确构建的扩展SCAM结构作为酶固定化的支撑基质。带负电荷的氨基脂肪酶PS与带正电荷的TUS 5之间的静电吸引力以及TUS 5的表面疏水性有助于脂肪酶与TUS 5基质的良好结合，此外还增强了脂肪酶的界面活化活性。利用有机和无机支撑基质的协同优势，其中有机支撑体具有成本效益、生物相容性以及改善的酶稳定性和可重复使用性，而无机支撑体具有高耐热性、机械抗性和抗微生物性，我们将固定在TUS 5 SCAM上的脂肪酶（脂肪酶@TUS 5）用于通过酯交换反应对（±）-1-苯乙醇进行动力学拆分。重要的是，与天然脂肪酶相比，脂肪酶@TUS 5除了具有优异的热稳定性、溶剂耐受性和可回收性外，还能实现更高的转化率生成（S）-1-苯乙酸乙酯。
