How do Molecules Self-Assemble into One-Dimensional Structures?

“该奖项是根据2009年《美国复苏和再投资法案》(公法111-5)资助的”。这个项目将研究为什么许多小分子在稀溶液中自组装，形成比人类头发还细的很长的“一维”(1D)物体，这些物体组织成三维(3D)网络。从几个分子聚集在一起开始生长过程的最早时刻开始，一直持续到一维物体完全形成的事件将被实验探测，并将开发出与结果一致的模型。将使用将分子和更宏观(即纤维)结构的时间演变以及生长模式相关联的技术来表征组装过程中的结构和动态变化。适当的理论计算将被用来模拟分子在纤维中的堆积，并将涵盖纤维生长所涉及的大空间和时间尺度。尽管研究的重点是特定的系统，但研究的主旨将是生成具有预测能力的全球模型。了解有机小分子如何以及为什么组装成一维物体和三维纤维网络，将使新的高科技纳米设备的设计和建造变得廉价。它将指出如何促进有益的生物功能(例如，细胞骨架细丝的形成)，以及如何阻止依赖纤维生长的神经退行性疾病(例如，阿尔茨海默氏症)。此外，一个推广项目将为华盛顿特区一所高中的学生带来纤维和凝胶形成的实际例子。这些模块将放在网上供一般使用。

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)". This project will investigate why many small molecules self-assemble in dilute solution to form very long "1-dimensional" (1D) objects, thinner than a human hair, that organize into 3-dimensional (3D) networks. Events starting from the earliest moments when a few molecules come together to start the growth process and continuing until the 1D objects are fully formed will be probed experimentally, and models consistent with the results will be developed. Structural and dynamic changes during the assembly process will be characterized using techniques that correlate the temporal evolution of molecular and more macro (i.e., fiber) structures, as well as growth patterns. Appropriate theoretical calculations will be used to model the packing of molecules within fibers and will cover the large space and time scales involved in the growth of fibers. Although focusing on specific systems, the thrust of the research will be to generate global models with predictive powers. Learning how and why small organic molecules assemble into 1D objects and in 3D fibrillar networks will enable the inexpensive design and construction of new high-tech nanodevices. It will indicate how to promote beneficial biological functions (e.g., cytoskeletal filament formation) and how to impede neurodegenerative diseases that rely on fibrillar growth (e.g., Alzheimer's). Also, an outreach project will bring practical examples of fiber and gel formation to students at a Washington, D.C. high school. The modules will be placed on the web for general use.