Polymer Conformation, Dynamics, Morphology

聚合物构象、动力学、形态

• 批准号: RGPIN-2017-03741
• 负责人: Winnik, Mitchell
• 金额: $ 9.03万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=668712
• 关键词: Polymer; Conformation; Dynamics; Morphology

My research is focused on developing new fundamental scientific knowledge about polymers as materials in areas where one can have an impact on modern technology or medicine. Much of our effort is devoted to the creation and study of polymer objects that form stable colloids in solution, with a uniform well-defined shape and with nanometer or micrometer dimensions. This proposal describes two broad projects, both in the area of polymer materials. One focuses on block copolymer self-assembly in solution. In collaboration with I. Manners (Bristol, UK) we have published seminal papers describing the unprecedented formation of nanofiber micelles in solution. This work has in many ways changed how scientists think about block copolymer micelle formation, particularly when the core-forming polymer is crystalline. In these studies, polyferrocenylsilane (PFS) was the core-forming block. It remains the only type of block copolymer that can form nanowires with a uniform and controllable length. Here I describe new experiments to understand mechanistically why and how such control of self assembly is possible, and how the PFS polymer molecules can fold as they add to the ends of the growing micelles to form crystals of such tiny dimensions. Because the growth of these nanofibers has key features in common with the formation of amyloid fibers associated with human diseases, but without the complications of fragmentation and aggregation, kinetic studies of PFS block copolymer micelle growth could provide important information about factors that affect nanofiber formation in solution. ******The other project is based on the idea that we can apply our extensive experience with rod-like colloidal nanostructures to test an idea in the current literature that nanosize rod-like drug delivery vehicles penetrate into tumors more effectively than spherical nanoparticles. We propose to prepare two types of rod-like nanocolloids in water, one based on cellulose nanocrystals and one based on PFS nanowire micelles. We will develop new chemistry to synthesize these nanorod colloids in which we will control the length of the rods, their cross section width, and their surface chemistry. Then, in collaboration with Prof C Allen (Pharmacy), my students will test the ability of these different structures to penetrate multicellular tumor spheroids, known to be good models for solid tumors in vivo, and compare the results with more traditional spherical nanoparticles. While the focus of these studies is entirely mechanistic, the results will have important implications for the application of these materials in nanomedicine.**

我的研究重点是在可能对现代技术或医学产生影响的领域发展有关聚合物的新基本科学知识。我们的大部分努力致力于创建和研究聚合物对象，这些聚合物物体在溶液中形成稳定的胶体，具有均匀定义的形状，纳米或千分尺尺寸。该提案描述了两个广泛的项目，均在聚合物材料的领域。一个专注于溶液中的块共聚物自组装。与I. Manners（英国布里斯托尔）合作，我们发表了开创性论文，描述了解决方案中纳米纤维胶束前所未有的形成。这项工作在许多方面都改变了科学家对块共聚物胶束形成的看法，尤其是当核心形成的聚合物是结晶时。在这些研究中，聚铁苯基硅烷（PFS）是核心形成块。它仍然是唯一可以形成具有均匀且可控长度的纳米线的块共聚物的类型。在这里，我描述了新的实验，以机械地了解这种对自组装的控制以及如何进行这种控制，以及PFS聚合物分子如何在添加到生长胶束的末端以形成这种微小维度的晶体时如何折叠。由于这些纳米纤维的生长具有与人类疾病相关的淀粉样蛋白纤维的形成具有关键特征，但是如果没有破碎和聚集的并发症，PFS的动力学研究可以阻止共聚物胶束的生长，可以提供有关影响溶液中纳米纤维形成的因素。 ******另一个项目是基于这样的想法：我们可以在杆状胶体纳米结构上运用丰富的经验来测试当前文献中的想法，即纳米化杆状药物输送车辆比球形纳米颗粒更有效地渗透到肿瘤中。我们建议在水中制备两种类型的棒状纳米胶样胶样胶样胶样胶样胶质样品，一种基于纤维素纳米晶体，另一种基于PFS纳米线胶束。我们将开发新的化学性质来合成这些纳米棒胶体，其中我们将控制杆的长度，它们的横截面宽度及其表面化学。然后，与C Allen教授（药房）合作，我的学生将测试这些不同结构穿透多细胞肿瘤球体的能力，这是体内实体瘤的良好模型，并将结果与​​更传统的球形纳米颗粒进行比较。尽管这些研究的重点完全是机械的，但结果将对这些材料在纳米医学中的应用具有重要意义。**