Structure, dynamics and mechanical properties of phytoglycogen nanoparticles: new insights into a novel sustainable nanomaterial

植物糖原纳米颗粒的结构、动力学和机械特性：对新型可持续纳米材料的新见解

• 批准号: RGPIN-2019-05004
• 负责人: Dutcher, John
• 金额: $ 3.64万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=715319
• 关键词: Structure; dynamics; mechanical; properties; phytoglycogen

Colloidal dispersions, in which microscopic or nanoscopic particles are suspended in a liquid, are ubiquitous in our everyday lives, ranging from foods to cosmetics to paints and inks to pharmaceuticals. The present research proposal focuses on elucidating the physical properties of a novel type of soft, deformable colloid, phytoglycogen nanoparticles. These particles were discovered in my laboratory and are isolated and purified from sweet corn. The highly-branched, tree-like structure of the particles gives rise to special properties that make them desirable for use in a wide range of applications in personal care, nutrition and biomedicine. To fully exploit these applications, it is necessary to understand in detail the complex physical properties of the particles, and my research group is leading the effort to do this. The present proposal focuses on understanding three different aspects of the particle properties: the soft glassy physics of concentrated dispersions, interactions between the particles, and interactions between the particles and other nanoparticles. We will do this by studying particles that we have modified using acid and enzymatic hydrolysis. These modifications will remove the hairy chains on the outer surface of the native particles and possibly modify the interior of the particles, changing their glassy dynamics, and the interactions between particles and with other nanoparticles. We will also chemically modify the particles with hydrophobic groups to achieve attractive interactions between the particles, and we will study the breakdown of the delicate gel-like structures that form in concentrated dispersions in the presence of these interactions, adding new insight into the nature of hydrophobic interactions. Modification of the particles with charged groups will enhance the repulsive interactions between the particles because of electrostatic effects. We will also study the interaction of phytoglycogen nanoparticles with metallic nanoparticles through physical association and compare this to the case in which the metallic nanoparticles are covalent bonded to the phytoglycogen nanoparticles. To accomplish this work, we will use a wide range of state-of-the-art sample preparation, microscopies, spectroscopies and scattering techniques. Our results will improve our understanding of the complex properties of this novel sustainable nanomaterial and, more generally, provide new insights into the complex relationship between thermodynamics, structure and dynamics of soft colloids. Our work will also help to identify and optimize new applications of this green, sustainable nanotechnology. Graduate and undergraduate students will receive unique, multidisciplinary training that will prepare them to contribute at a very high level for a variety of careers in academia, government and industry.

胶体分散体，其中微米或纳米粒子悬浮在液体中，在我们的日常生活中无处不在，从食品到化妆品，从油漆和油墨到药品。本研究计划的重点是阐明一种新型柔软、可变形胶体植物糖原纳米颗粒的物理特性。这些颗粒是在我的实验室中发现的，是从甜玉米中分离和纯化的。颗粒的高度支化、树状结构产生了特殊的性质，使其在个人护理、营养和生物医学领域的广泛应用中得到理想的应用。为了充分利用这些应用，有必要详细了解粒子的复杂物理特性，我的研究小组正在领导这方面的工作。本提案侧重于理解颗粒特性的三个不同方面：浓缩分散体的软玻璃态物理、颗粒之间的相互作用以及颗粒与其他纳米颗粒之间的相互作用。我们将通过研究使用酸和酶水解改性的颗粒来做到这一点。这些修饰将去除天然颗粒外表面上的毛状链，并可能改变颗粒的内部，改变它们的玻璃态动力学以及颗粒之间以及与其他纳米颗粒之间的相互作用。我们还将用疏水基团对颗粒进行化学修饰，以实现颗粒之间有吸引力的相互作用，并且我们将研究在存在这些相互作用的情况下在浓缩分散体中形成的精致凝胶状结构的分解，从而为了解颗粒的性质提供新的见解。疏水相互作用。由于静电效应，用带电基团对颗粒进行改性将增强颗粒之间的排斥相互作用。我们还将通过物理缔合研究植物糖原纳米颗粒与金属纳米颗粒的相互作用，并将其与金属纳米颗粒共价键合到植物糖原纳米颗粒的情况进行比较。为了完成这项工作，我们将使用各种最先进的样品制备、显微镜、光谱和散射技术。我们的研究结果将增进我们对这种新型可持续纳米材料复杂特性的理解，更广泛地说，为软胶体的热力学、结构和动力学之间的复杂关系提供新的见解。我们的工作还将有助于确定和优化这种绿色、可持续纳米技术的新应用。研究生和本科生将接受独特的多学科培训，使他们做好准备，为学术界、政府和工业界的各种职业做出高水平的贡献。