Elucidating Bio-Nano Interface Atomic Structure and Peptide Directed Nanoparticle Formation

在化学系大分子、超分子和纳米化学计划的支持下，圣地亚哥州立大学的Gregory Holland正在发展对纳米生物界面的原子和分子结构的理解，以及纳米颗粒曲率、介孔和形貌对纳米颗粒表面生物分子配体结构、动力学和组织的影响。无机核和生物分子配体涂层在结构上是不同的实体，但它们相互强烈影响，协同决定了纳米粒子系统的集体性质。感兴趣的系统包括一系列具有不同形态和自然激发的羟基磷灰石纳米材料的二氧化硅纳米结构，这些纳米材料具有蛋白质和脂类配体的功能。阐明生物分子在纳米材料上组装的原子、分子和纳米尺度的细节，开发新型的多肽导向纳米颗粒合成，以及了解生物分子在纳米颗粒上的表面化学是研究的重点。这种基本的化学知识可能有助于开发将纳米材料与生物分子功能相结合的下一代设备和传感器。该项目正在为各级学生创造宝贵的研究培训机会，并进一步与外联活动的发展相结合。霍兰德博士正在建立一个关于纳米粒子表面表征的高度跨学科的研究和教育计划，包括研究生、本科生和高中实习生的广泛参与，为培训多样化的劳动力做出贡献。绝大多数化学合成和自然生成的纳米结构，无论其化学成分、无机核心、形态和结晶度，都覆盖着配位体外壳。这项研究的主要目标是确定纳米生物界面的原子和分子水平结构，并在纳米粒子合成策略中利用生物分子，包括多肽和脂类作为配体。主要有两个重点：(1)研究组装在一系列纳米结构二氧化硅上的生物分子，包括胶体单分散球、高度缺陷的支化气相二氧化硅和介孔二氧化硅纳米颗粒，其中包裹在纳米孔中的生物分子的行为是重点；(2)以多肽为模板合成的天然羟基磷灰石纳米棒和纳米片。这项研究将结合物理/分析技术，包括固体核磁共振光谱、电子显微镜和分子动力学模拟(MDS)来确定多肽和脂类在这些体系界面上的结构和组装，并阐明纳米粒子的曲率和形态对配体结构的影响。这项工作正在扩展全球纳米科学界可用的合成和表征方法，以改善对纳米生物结构的基本了解。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Gregory Holland of San Diego State University is developing atomic and molecular level structural understanding of nano-bio interfaces and the influence of nanoparticle curvature, mesoporosity and morphology on biomolecular ligand structure, dynamics and organization on nanoparticle surfaces. The inorganic cores and the biomolecular ligand coatings are structurally distinct entities but strongly influence each other synergistically determining the collective properties of the nanoparticle system. The systems of interest include a range of silica nanostructures with varying morphology and naturally inspired hydroxyapatite nanomaterials functionalized with protein- and lipid-based ligands. Elucidating the atomic, molecular and nanoscale detail of biomolecular assembly on nanomaterials, developing novel peptide-directed nanoparticle syntheses and understanding the surface chemistry of biomolecules on nanoparticles is the research focus. This fundamental chemical knowledge could contribute to the development of next generation devices and sensors that couple nanomaterials with biomolecular functionality. The project is creating valuable research training opportunities for students at various levels that is further integrated with outreach activity development. Dr. Holland is building a highly interdisciplinary research and education program on nanoparticle surface characterization involving broad participation of graduate, undergraduate and High School interns contributing to the training of a diverse workforce.The vast majority of chemically synthesized and naturally occurring nanostructures, regardless of their chemical compositions, inorganic core, morphology and crystallinity, are coated with a ligand shell. The primary goal of this research is to determine the atomic and molecular level structure of nano-bio interfaces and to exploit biomolecules, including peptides and lipids as ligands in nanoparticle synthetic strategies. There are two main foci: (1) to investigate biomolecules assembled on a range of nanostructured silicas including colloidal monodisperse spheres, highly defective, branched fumed silica, and mesoporous silica nanoparticles where the behavior of biomolecules encapsulated within nanopores is the focus; and (2) naturally inspired hydroxyapatite nanorods and nanosheets synthesized with peptides as the templating agents. A combination of physical/analytical techniques will be used in the research, including solid-state NMR spectroscopy, electron microscopy and molecular dynamics simulation (MDS) to determine the structure and assembly of peptides and lipids at the interface of these systems and elucidate the influence of nanoparticle curvature and morphology on ligand architecture. This work is expanding on the synthetic and characterization methods available to the global nanoscience community for improved fundamental understanding of nano-biostructures.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.