Collaborative Research: Self-regulated non-equilibrium assembly of chiral colloidal clusters via electrokinetic interactions

合作研究：通过动电相互作用实现手性胶体簇的自我调节非平衡组装

• 批准号: 2314340
• 负责人: Hui Zhao
• 金额: $ 25.75万
• 依托单位: University of Nevada Las Vegas
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2314340&HistoricalAwards=false
• 关键词: Collaborative; Research; Self; regulated; non

Non-technical abstract Autonomous motion and transport of microscopic objects are essential for maintaining the bioactivities of all living species. Although natural systems have evolved to possess extremely delicate biochemical motors, the development of synthetic motors lags way behind in complexity and efficiency. This research aims to provide the fundamental knowledge necessary for developing new types of synthetic microrobots driven by non-invasive alternating-current electric fields. In particular, the research team investigates the interplay between two types of electric-field-induced solvent flow surrounding microscopic particles. Precise control of such kind of particle interactions provides a new mechanism for cargo capture, transport, and delivery by the colloidal micromotors in a lab-on-a-chip device. Moreover, the organized structures formed by those micromotors are excellent building blocks for making functional materials that exhibit exotic optical properties for applications in superlenses, cloaking devices, and molecular sensing. In addition, this award also plans to develop hands-on learning modules to engage underrepresented groups in science and engineering. Technical abstract This project aims to answer a fundamental question in colloidal physics: what is the nature of the electrokinetic flow around a charged dielectric particle near an electrode when subjected to a perpendicularly applied alternating-current electric field? A series of recent experiments strongly suggest that the classical theories on electrohydrodynamic flow and induced-charge electroosmosis flow are insufficient to capture the propulsion and non-equilibrium assembly of charged dielectric particles because it only considers the electroosmotic flow originating from the electrode. Instead, this project investigates the impact of the concentration polarization of the electric double layer around the charged particle on a new type of electrokinetic flow (the concentration-polarization-induced electroosmosis) via complementary experimental and theoretical studies. In addition, the hydrodynamic interactions originating from multiple types of electrokinetic flow are exploited to achieve the self-regulated out-of-equilibrium assembly of multiple colloids into uniform clusters with complex symmetries. Finally, perturbation theory and Brownian dynamics simulations are used to investigate the role of hydrodynamic interactions in the assembly.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术抽象的自主运动和微观物体的运输对于维持所有活物种的生物活性至关重要。尽管天然系统已经发展为具有极其细腻的生化电动机，但合成电动机的发展落后于复杂性和效率。这项研究旨在提供开发由非侵入性交流电场驱动的新型合成微型机器人所需的基本知识。特别是，研究小组研究了两种类型的电场诱导的溶剂流动围绕微观颗粒之间的相互作用。这种类型的粒子相互作用的精确控制为通过实验室芯片设备中的胶体微型运动器捕获，运输和传递提供了一种新的机制。此外，这些微动物形成的有组织的结构是制造功能材料的极好的构件，用于在超镜头，隐身装置和分子传感的应用中具有外来的光学特性。此外，该奖项还计划开发动手学习模块，以吸引代表性不足的科学和工程团体。技术摘要该项目旨在回答胶体物理学中的一个基本问题：当受到垂直施用交替电流电场时，电动电极附近带电介电粒子周围电动流动流的性质是什么？一系列最近的实验强烈表明，有关电水力动力学流量和诱导式电流电流流的经典理论不足以捕获带电介电颗粒的推进和非平衡组装，因为它仅考虑了源自电极的电流流。取而代之的是，该项目通过补充实验和理论研究研究了带电粒子周围电动双层浓度极化对新型电动流动流（浓度极化引起的电肿瘤）的影响。另外，利用源自多种电动流动流的流体动力相互作用，以实现多个胶体的自我调节外部组装，将多个胶体的异常组装成具有复杂对称性的均匀簇。最后，使用扰动理论和布朗动力学模拟来调查流体动力相互作用在大会中的作用。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响审查标准，被认为值得通过评估来支持。