Metalloenzyme Mimics with Unsupported Metal Nanoparticle Catalysts

 描述（由申请人提供）：基于配体封端的金属纳米颗粒的扩散原理的均相催化最近在其作为酶模拟物的潜力方面引起了更多的兴趣，这是生物技术和医学研究领域中最优先的领域之一。特别是，简单模型纳米结构材料在增强或抵抗类似于酶的特定底物的吸附方面的能力需要进行积极的研究。我们的研究小组最近开发了一种新的催化体系，对烯烃和炔的异构化和/或加氢具有优异的活性和选择性。考虑到它们的尺寸（总粒径为6-8 nm）、球形形状和多功能配体特性，这些具有活性催化金属核的精心设计的有机配体封端的纳米颗粒的可用性将特别有利于基于纳米颗粒的金属酶模拟物的进步。例如，通过在有机配体的烃链的“尾部”中引入不同的疏水官能团，我们可以以类似于改变酶结合口袋中的氨基酸残基（侧基）的方式调节近表面环境中的空间和/或非共价相互作用。这种方法将允许研究表面固定化配体在细胞表面上的能力。 通过这些分子间的相互作用精确地调节催化选择性。拟议的为期四年的SCORE SC 3研究计划将侧重于了解近表面空间控制，非共价相互作用和手性相互作用如何确定改性纳米颗粒对与生物重要转化（烯烃还原和异构化）相关的模型有机反应的催化性能。申请的资金为PI提供夏季和学术支持，支持1名学士后研究员或技术员/年，化学品，用品，研究活动的实验室消耗品和传播的差旅费。 本论文的主要工作包括四个方面：1）具有近表面空间位阻的金属酶模拟物，用于化学选择性和区域选择性反应。2)具有非共价相互作用的金属酶模拟物，用于化学选择性和区域选择性反应。3)具有手性相互作用的金属酶模拟物在立体选择性反应中的应用。4)具有受控表面配体极性的金属酶模拟物，用于水中的生物重要反应。 这 研究计划将允许PI发展基础和转化研究技能，成为纳米材料结构控制，材料表征和金属酶模拟物的独立专家，用于生物学上重要的转化。同时，该计划将提供研究生（M.S.水平，2名学生/年）和本科生（4名学生/年）在纳米技术的独特和令人兴奋的研究机会。通过在现有的研究为基础的课程招生，学生将有机会成为一个跨学科的研究计划，将在这个项目的各个方面合作的参与者-从开始，从基本的纳米颗粒材料合成开始，到完成，最终 评价这些新的金属酶模拟物的催化性能。他们还将开发批判性分析现有信息的智力能力，并开发复杂数据集的分析，解释和演示的熟练程度。PI将积极 招收女性和/或少数民族学生，传统上在化学中代表性不足的群体，以加强研究和教育的平衡发展（CSULB被指定为西班牙裔服务机构）。PI在参与少数民族本科生研究项目（如BUILD）方面有着良好的记录（NIH资助建设基础设施，实现多样性）、MARC（少数人获得研究职业由NIH资助），RISE（美国国立卫生研究院资助的科学增强研究倡议），桥（美国国立卫生研究院资助的学士学位桥梁），除了LSAMP（由NSF资助的Louis Stokes少数民族参与联盟计划）之外，CSULB目前还提供。

 DESCRIPTION (provided by applicant): The homogeneous catalysis based on the principle of diffusion of ligand-capped metal nanoparticles has recently drawn more interest as regards to its potential as enzyme mimics, which are one of the highest priority areas in the field of biotechnology and medical research. In particular, the ability of simple model nanostructured materials in enhancing or resisting the adsorption of particular substrates similar to that of enzymes is in needs of active investigation. Our research group has recently developed a new catalytic system that exhibits excellent activity and selectivity for the isomerization and/or hydrogenation of alkenes and alkynes. Considering their size (6-8 nm in overall particle diameter), spherical shape, and versatile ligand characteristics, the availability of these well-designed organic ligand-capped nanoparticles with active catalytic metal core will especially benefit the advancement in nanoparticle-based metalloenzyme mimics. For example, by introducing different hydrophobic functional groups in the "tail" of hydrocarbon chains of organic ligands, we can adjust steric and/or non-covalent interactions in the near-surface environment in a manner analogous to changing amino acid residues (side groups) in an enzyme binding pocket. This approach will allow the investigation of the ability of surface immobilized ligands on precisely tuning catalytic selectivity through these molecular interactions. The proposed four-year SCORE SC3 research program will focus on understanding how near-surface steric controls, non-covalent interactions, and chiral interactions determine the catalytic properties of the modified nanoparticles towards the model organic reactions relevant to the biologically important transformations (olefin reduction and isomerization). Requested funding provides summer and academic support for the PI, support for 1 post-baccalaureate fellow or technician/year, chemicals, supplies, lab consumables for research activity, and travel expenses for dissemination. The work involves four major tasks: 1) Metalloenzyme mimics with near-surface steric controls for chemo selective and regioselective reactions. 2) Metalloenzyme mimics with non-covalent interactions for chemo selective and regioselective reactions. 3) Metalloenzyme mimics with chiral interactions for stereo selective reactions. 4) Metalloenzyme mimics with controlled surface ligand polarity for biologically important reactions in water. This research plan will allow the PI to develop the basic and translational research skills to become an independent expert in nanomaterials structure controls, materials characterizations, and metalloenzyme mimics for biologically important transformations. Simultaneously, this program will provide graduate (M.S.-level, 2 students/year) and undergraduate students (4 students/year) with unique and exciting research opportunities in nanotechnology. Through enrollment in existing research-based classes, students will be offered the opportunity to be participants in an interdisciplinary research program that will collaborate on all aspects of this project - from inception, starting with basic nanoparticulate material synthesis, to completion, with the ultimate evaluation of the catalytic performance of these new metalloenzyme mimics. They will also develop the intellectual capacity to critically analyze existing information as well as develop proficiency in the analysis, interpretation and presentation of complex data sets. PI will actively recruit females and/or minority students, traditionally underrepresented groups in chemistry, to enhance the balanced advancement of research and education (CSULB is designated as a Hispanic Serving Institution). PI has a good track record of participating minority undergraduate research programs such as BUILD (Building Infrastructure Leading to Diversity funed by NIH), MARC (Minority Access to Research Careers funded by NIH), RISE (Research Initiative for Scientific Enhancement funded by NIH), BRIDGES (Bridges to the Baccalaureate funded by NIH), in addition to LSAMP (Louis Stokes Alliance for Minority Participation program funded by NSF) that are currently available in CSULB.