Artificial Enzymes: Development of Biomimetic Catalysts in Metal-Organic Frameworks

人工酶：金属有机框架仿生催化剂的开发

• 批准号: 9397216
• 负责人: Christine N Morrison
• 金额: $ 5.63万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-12-01 至 2020-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9397216
• 关键词: Acetylene; Acids; Ammonia; Anabolism; Binding; Biological Markers; Biomimetic Materials; Biomimetics; Catalysis; Catalytic Domain; Complex; Development; Electrons; Enzymes; Ethylenes; Health; Human; Hydrogen; Hydrogenase; Industrialization; Ligands; Metalloproteins; Metals; Methods; Modeling; Natural Gas; Nitrogenase; Outcome; Photosensitization; Photosensitizing Agents; Planet Earth; Production; Proteins; Protons; Reaction; Reducing Agents; Reporting; Research; Sampling; Scheme; Site; Technology; Testing; Work; biological systems; biomaterial compatibility; catalyst; design; insight; molecular hydrogen; oxidation; small molecule

PROJECT SUMMARY/ABSTRACT This research aims to create new metal-organic frameworks with FeS clusters modeled from metalloproteins. Using earth-abundant, biocompatible metals such as Fe in the biomimetic catalysts will enhance health by contributing to the development of materials that may be used on human samples for applications such as sensing biological markers. More specifically, successful synthesis of the proposed materials will allow for the catalysis of more complex and wide-ranging reactions in artificial enzymes. Two related projects are proposed. First, a biomimetic MOF containing [2Fe:2S] clusters and photosensitizers that can efficiently catalyzes the reduction of protons to molecular hydrogen will be constructed. A few examples of [2Fe:2S]-MOFs are reported; however, they have not been optimized for efficient catalysis. Using a recently presented MOF called PCN-700, a linker containing a [2Fe:2S] cluster and another containing a photosensitizer will be postsynthetically installed in the PCN-700 framework to yield a catalytic MOF. These [2Fe:2S]-MOFs can then be easily tuned for catalytic efficiency by installing a third linker that is functionalized to control polar contacts within the MOF. Second, MOFs containing [4Fe:4S] clusters will be synthesized and assessed for catalytic activity. Successful inclusion of [4Fe:4S] clusters in a MOF would expand the catalytic and/or biomimetic potential of MOFs by utilizing the additional available oxidation states afforded by the four Fe sites compared to smaller FeS clusters. For example, more complex reactions could be carried out, such as those requiring four or more electrons. Also, since [4Fe:4S] clusters can bind reaction intermediates (which has not been demonstrated with [2Fe:2S] clusters in a protein), the [4Fe:4S]-MOFs may be used to study reaction intermediates that have not been successfully characterized using the biological system or small molecules. Two approaches are proposed for synthesizing [4Fe:4S]-MOFs. First, free [4Fe:4S] clusters will be synthesized with -SCH3 groups on each Fe. These SCH3 ligands will be exchanged with the bifunctional linker 4,4’-biphenyldithiol to yield a framework, in the presence of reductant and acid. The second synthetic approach involves assembling the FeS clusters and the framework simultaneously by using 4,4’-biphenyldithiol instead of HSCH3 in the scheme originally designed for synthesizing free [4Fe:4S] clusters. Overall, the results of this work will advance the field of biomimetic catalysts using FeS clusters. The proposed [2Fe:2S]-MOFs will be optimized for catalytic activity, and the proposed [4Fe:4S]-MOFs would be the first of their kind, thereby introducing a new class of biomimetic catalysts.

项目摘要/摘要 这项研究旨在使用以FES簇为模型的FES簇来创建新的金属有机框架 金属蛋白。使用含有地球的生物相容性金属，例如仿生催化剂中的Fe 通过为人类样本中使用的材料的开发做出贡献来提高健康 诸如敏感生物标记等应用。更具体地，成功合成了提议的 材料将允许在人工酶中催化更复杂和更宽的反应。 提出了两个相关项目。首先，含有[2FE：2S]簇的仿生MOF和 可以有效地催化质子还原为分子氢的光敏剂将是 构造。报告了一些[2FE：2S] -MOF的例子；但是，它们尚未针对 有效的催化剂。使用最近呈现的MOF，称为PCN-700，一个包含[2FE：2S]群集的链接器和 在PCN-700框架中，将在pcn-700框架中安装了另一个包含光敏剂的另一个 催化MOF。然后，可以通过安装第三个链接器来轻松调节这些[2FE：2S] -MOF的催化效率 该功能可以控制MOF内的极性接触。 其次，将合成含有[4FE：4S]簇的MOF，并评估催化活性。 成功将[4FE：4S]簇纳入MOF将扩大催化和/或仿生潜力 通过使用四个FE站点提供的其他可用氧化状态MOF，而较小 FES集群。例如，可以进行更复杂的反应，例如需要四个或更多的反应 电子。同样，由于[4FE：4S]簇可以结合反应中间体（尚未证明 [2fe：2s]蛋白质中的簇），[4FE：4S] -MOF可用于研究尚未的反应中间体 我们通过生物系统或小分子成功表征了我们。提出了两种方法 用于合成[4FE：4S] -MOFS。首先，免费[4fe：4s]簇将与-sch3组合成 铁。这些SCH3配体将与4,4'biphenyldithiol的双功能连接器交换以产生一个框架， 在还原和酸的情况下。第二种合成方法涉及组装FES簇 并且仅通过在该方案中使用4,4'-Biphenyldithiol而不是HSCH3来最初使用框架 设计用于合成免费的[4FE：4S]簇。 总体而言，这项工作的结果将使用FES簇推进仿生催化剂的领域。这 提出的[2FE：2S] -MOF将针对催化活性进行优化，并且建议的[4FE：4S] -MOF将是 首先，从而引入了一类新的仿生催化剂。