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.

项目总结/摘要 这项研究的目的是创造新的金属有机框架与FeS集群模拟从 金属蛋白在仿生催化剂中使用地球上丰富的生物相容性金属，如Fe， 通过促进开发可用于人体样本的材料， 例如传感生物标记的应用。更具体地说，成功地合成了所提出的 材料将允许在人造酶中催化更复杂和更广泛的反应。 提出了两个相关项目。首先，仿生MOF含有[2Fe：2S]簇和 可以有效地催化质子还原为分子氢的光敏剂将被 构建了报道了[2Fe：2S]-M0 F的几个实例;然而，它们尚未被优化用于 高效催化使用最近提出的称为PCN-700的MOF，使用含有[2Fe：2S]簇和[2Fe：2S]簇的连接体， 另一种含有光敏剂的将在合成后安装在PCN-700框架中，以产生 催化MOF。这些[2Fe：2S]-MOFs然后可以通过安装第三接头容易地调节催化效率 其被官能化以控制MOF内的极性接触。 其次，将合成含有[4Fe：4S]簇的MOFs并评估其催化活性。 在M0 F中成功包含[4Fe：4S]簇将扩大M0 F的催化和/或仿生潜力。 通过利用由四个Fe位点提供的额外的可用氧化态，与较小的Fe位点相比， FeS团簇。例如，可以进行更复杂的反应，例如需要四个或更多个反应的那些反应。 电子。此外，由于[4Fe：4S]簇可以结合反应中间体（这还没有被证明与 [2Fe：2S]簇），[4Fe：4S]-M0 Fs可用于研究不具有以下性质的反应中间体： 已经成功地使用生物系统或小分子进行了表征。提出了两种方法 用于合成[4Fe：4S]-MOFs。首先，自由的[4Fe：4S]簇将被合成，每个簇上具有-SCH 3基团。 菲。这些SCH 3配体将与双官能接头4，4 ′-联苯二硫醇交换以产生骨架， 在还原剂和酸的存在下。第二种合成方法涉及组装FeS簇 用4，4 ′-联苯二硫醇代替原方案中的HSCH 3， 设计用于合成游离[4Fe：4S]簇。 总之，这项工作的结果将推进仿生催化剂领域使用硫化亚铁簇。的 提出的[2Fe：2S]-MOFs将优化催化活性，而提出的[4Fe：4S]-MOFs将是最佳的催化剂。 这是同类产品中的第一个，从而引入了一类新的仿生催化剂。