Coating Effects on MR Relaxivities: Dendron-Iron Oxide Nanoparticle Models

涂层对 MR 弛豫率的影响：Dendron-氧化铁纳米颗粒模型

• 批准号: 7190449
• 负责人: Boyd M Goodson
• 金额: $ 21.68万
• 依托单位: SOUTHERN ILLINOIS UNIVERSITY CARBONDALE
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-01 至 2010-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7190449
• 关键词: Anti-HIV Agents; Applications Grants; Area; Attention; Biocompatible Coated Materials; Biological Models; Blood Circulation; Cations; Characteristics; Charge; Chemicals; Class; Classification; Clinical; Collaborations; Communities; Condition; Contrast Media; Dendrimers; Detection; Diagnosis; Electrostatics; Environment; Evaluation; Extravasation; Funding; Future; Gadolinium; Grant; Housing; Human; Investigation; Investments; Knowledge; Laboratories; Magnetic Resonance; Magnetic Resonance Imaging; Magnetism; Malignant Neoplasms; Melamine; Metals; Modality; Modeling; Molecular; Molecular Weight; Nucleosome Core Particle; Organic Synthesis; Pathology; Personal Satisfaction; Polymers; Principal Investigator; Process; Property; Rate; Reaction; Relative (related person); Relaxation; Reporting; Research; Route; Shapes; Solubility; Specificity; Structure; Study models; Surface; Surface Properties; Techniques; Tissues; United States Food and Drug Administration; United States National Institutes of Health; Universities; Variant; Washington; Water; aqueous; base; cytotoxicity; density; improved; in vivo; iron oxide; macromolecule; medical schools; nanocomposite; nanocrystal; nanoparticle; novel; particle; prevent; programs; self assembly; size; soft tissue; success; uptake

DESCRIPTION (provided by applicant): Uncovering the relationship between the surface structure and magnetic resonance relaxivities of iron oxide nanoclusters is key to improving the contrast specificity and expanding applicability of this class of contrast agents. The surface properties of iron oxide nanoparticles have enormous effects on the overall magnetic characteristics that determine the particles' relaxation properties. The symmetry at the iron oxide surface is reduced for the chemical surroundings of magnetic metal cations due to the incomplete coordination sphere, and properties of the nanoparticle surfaces are usually different from those within the body nanoparticle. As the size of nanoparticles decreases, the influence of surface interactions magnetic properties of the nanoparticles becomes more significant due to the increased fraction of surface atoms within the particle. Additionally, the coating properties can modulate surface access of water molecules, the particle hydrodynamic size, tumbling rate, solubility, microscale clustering, tissue uptake, and/or intracellular partitioning. However, due to the lack of a model system that has vigorous controls of both its surface core characteristics, detailed investigations of the relationships between structural parameters surface and the relaxivities of iron oxide nanoparticles are still limited. We believe that dendron protected iron oxide nanoparticles can be developed into a novel model for systematically the surface effects on MR relaxation properties. The synthesis of dendrons will be achieved conventional multiple-step organic syntheses in a controlled, defined, and discrete manner. structure of the shell coatings of dendron-iron oxide nanoparticles can be precisely constructed regulated. In addition, due to their dendron coatings, dendron-iron oxide nanoparticles unique class of contrast agents offering many potential advantages over conventional counterparts. For example, when injected intravenously, the leakage of dendron-based the bloodstream into other bodily compartments can potentially be tuned by varying the molecular weight, coverage, and functionality of the dendrons. Our AREA (R15) grant application has set up two specific aims: (1) developing new routes for constructing dendron-coated iron oxide nanoparticles that have various surface electrostatics and other properties; and (2) examining the NMR relaxation-inducing properties dendron-iron oxide nanoparticles in bulk and cellular environments, particularly regarding effects. We believe that this medium-sized R15 grant would be a high-value investment for an important area that has not received much attention from the MR community.

描述（由申请人提供）：揭示氧化铁纳米团簇的表面结构与磁共振弛豫率之间的关系是提高这类造影剂的造影剂特异性和扩大其适用性的关键。氧化铁纳米粒子的表面性质对决定粒子弛豫特性的整体磁性特性有巨大的影响。在磁性金属阳离子的化学环境下，由于配位球不完全，导致氧化铁表面的对称性降低，纳米颗粒表面的性质往往与体内纳米颗粒的性质不同。随着纳米粒子尺寸的减小，纳米粒子的表面相互作用磁性能的影响变得更加显著，这是由于粒子内表面原子的比例增加。此外，涂层性能可以调节水分子的表面进入、颗粒流体动力学大小、翻滚速率、溶解度、微尺度聚类、组织摄取和/或细胞内分配。然而，由于缺乏一个能有效控制其表面核特征的模型系统，对氧化铁纳米颗粒结构参数、表面和弛豫率之间关系的详细研究仍然有限。我们相信树突保护的氧化铁纳米颗粒可以发展成为系统研究表面效应对MR弛豫特性的新模型。树突的合成将以控制、定义和离散的方式实现传统的多步骤有机合成。树突-氧化铁纳米颗粒的壳层结构可以被精确地构建和调控。此外，由于树突涂层，树突氧化铁纳米颗粒是一种独特的造影剂，与传统的造影剂相比，具有许多潜在的优势。例如，当静脉注射时，以树突为基础的血液渗漏到其他身体隔室，可以通过改变树突的分子量、覆盖范围和功能来潜在地调节。我们的区域（R15）拨款申请设立了两个具体目标：(1)开发新的路线来构建树突涂层的氧化铁纳米颗粒，这些纳米颗粒具有各种表面静电和其他特性；(2)研究树突氧化铁纳米颗粒在体和细胞环境中的核磁共振弛豫诱导特性，特别是在影响方面。我们相信，这笔中等规模的R15拨款将是对一个重要领域的高价值投资，该领域尚未受到MR社区的太多关注。