CAREER: A Research and Teaching Program in Complex Fluids Dynamics

9623972 Wirtz这项职业基金的主要研究目标是建立一个突出的项目，重点是复杂流体和大分子的动力学。正在发展新的实验、数值和理论方法来研究复杂流体和大分子组件的结构和动力学。这些实验方法包括测量单个聚集体或分子(显微镜)或胶体/大分子整体的结构和流变性(散射和流变学)。这些实验方法包括：(I)用磁镊子对单个生物大分子如DNA和蛋白质进行微观操作，(Ii)用高分辨率荧光显微镜成像单个生物大分子、小泡和胶体聚集体的布朗运动；(Iii)用扩散波光谱仪探测浓缩胶体悬浮液、微乳液和聚合物溶液的集体动力学和静态微流变学。为了分析这些散射和显微实验，蒙特卡罗模拟和分子动力学模拟以及随机运动方程被用来描述复杂流体和大分子在外力场中的非平衡动力学。这项研究将为凝胶电泳理论提供直接的检验，并将有助于改进目前的基因治疗和基于聚合物的药物输送系统的理论。这些新工具还将提供一种直接的方法来探测DNA-DNA、蛋白质-DNA和蛋白质-蛋白质相互作用引起的构象和运输性质的变化，这些变化对新药的设计、开发和测试具有重要意义。***

9623972 Wirtz The main research objective of this CAREER grant is to establish a prominent program with a focus on the dynamics of complex fluids and macromolecules. Novel experimental, numerical, and theoretical methods are being developed to investigate the structure and dynamics of complex fluids and macromolecular assemblies These experimental methods involve the measurement of the structural and rheological properties of either individual aggregates or molecules (microscopy) or of an ensemble of colloids/macromolecules (scattering and rheology). These experimental methods include (i) magnetic tweezers to micro-manipulate individual biological macromolecules such as DNA and proteins in the bulk and near interfaces, (ii) high-resolution fluorescence microcopy to image the Brownian motion of individual biological macromolecules, vesicles, and colloidal aggregates (iii) diffusive wave spectroscopy to probe the collective dynamics and the quiescent micro-rheology of concentrated colloidal suspensions, microemulsions, and polymer solutions. To analyze these scattering and microscopy experiments, Monte Carlo and molecular dynamics simulations, as well as stochastic equations of motion are being developed to describe the non-equilibrium dynamics of complex fluids and macromolecules in external force fields. %%% This research will provide a direct test of theories of gel electrophoresis and will help improve current theories of gene therapy and polymer-based drug-delivery systems. These new tools will also offer a direct way to probe conformational and transport-properties changes induced by DNA-DNA, protein-DNA, and protein-protein interactions, which have implications on the design, development, and testing of new drugs. ***