CAREER: Symmetry-based microfluidics and perturbation-free micromanipulations of swimming microorganisms

职业：基于对称性的微流体和游动微生物的无扰动显微操作

• 批准号: 2046822
• 负责人: Bin Liu
• 金额: $ 50.83万
• 依托单位: University of California - Merced
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2046822&HistoricalAwards=false
• 关键词: CAREER; Symmetry; based; microfluidics; perturbation

Precise control of fluid flow in small geometries, or microfluidics, has been used as a powerful means of controlling or transporting small particles. Microfluidics can be potentially used to manipulate microorganisms to study how they sense the mechanical properties of their environment (mechanosensation). Gaining a full understanding of the mechanosensation of these microorganisms may lead to mechanical control of their behavior as an alternative to the traditional chemical treatments in ecological, environmental, and health applications. The advancement in microfabrication techniques has yielded increasingly sophisticated geometries in microfluidic devices, and the flow within these devices can be predicted using computational fluid dynamics. This project explores the fundamental principles that govern microfluidic flows relevant to micromanipulation of microorganisms, using a technique called symmetry-based abstraction. Advanced microfluidics and three-dimensional imaging techniques developed for this project can be directly transferable to many biological, medical, and industrial applications. The proposed endeavor also consists of notable educational components, including “Virtual Imaging Lab” and “Kirigami-Origami Microfluidics” outreach programs that bring interactive research experiences to both the regular classroom and virtually to the public.The goal of this project is to establish a symmetry-based framework of understanding and then modulating microscale flow patterns for advanced micromanipulations. This level of controlled microfluidic environment will be used for isolating the passive mechanical responses of microorganisms to surrounding media from active responses. This functionality will elevate our understanding of the mechanical effects and lead to mechanical treatments for biological controls. The approach is to (i) develop and experimentally measure a symmetry-based foundation of microfluidics for advanced manipulation functions, (ii) extend these capabilities to perturbation-free manipulations of living cells (by building a “bacterial treadmill”), and (iii) ultimately realize channel-free and pixelated microfluidic applications. By bridging flow patterns and flow symmetries, a broader design space of microfluidics beyond simple geometries is made available for advanced microfluidic applications. By robustly isolating the microorganisms from mechanical perturbations through flow symmetries, a controlled comparison of microorganisms under perturbation-free and mechanically perturbed conditions becomes viable. This comparison will quantitatively provide the mechanoresponses of microorganisms to surrounding media. This understanding also provides us a rigorous approach to explore the true hydrodynamic effects of swimming microorganisms.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.

精确控制小几何形状或微流体中的流体流动已被用作控制或输送小颗粒的有力手段。 微流体技术可用于操纵微生物，以研究它们如何感知环境的机械特性（机械感知）。 充分了解这些微生物的机械感觉可能会导致其行为的机械控制，作为生态，环境和健康应用中传统化学处理的替代方案。 微制造技术的进步已经在微流体装置中产生了越来越复杂的几何形状，并且可以使用计算流体动力学来预测这些装置内的流动。 该项目探索了与微生物显微操作相关的微流体流动的基本原理，使用一种称为基于微流体的抽象技术。为该项目开发的先进微流体和三维成像技术可以直接转移到许多生物，医学和工业应用中。该奋进还包括“虚拟成像实验室”和“Kirigami-Origami Microfluidics”外展计划，这些计划将互动研究经验带到普通课堂和虚拟公众中。该项目的目标是建立一个基于生物学的框架，了解并调节微尺度流动模式，以实现先进的显微操作。这种水平的受控微流体环境将用于将微生物对周围介质的被动机械响应与主动响应隔离。该功能将提升我们对机械效应的理解，并导致生物控制的机械处理。该方法是（i）开发和实验测量用于高级操作功能的微流体的基于微流控的基础，（ii）将这些能力扩展到活细胞的无扰动操作（通过构建“细菌跑步机”），以及（iii）最终实现无通道和像素化微流控应用。通过桥接流动模式和流动对称性，超越简单几何形状的更广泛的微流体设计空间可用于先进的微流体应用。通过通过流动对称性将微生物与机械扰动稳健地隔离，在无扰动和机械扰动条件下的微生物的受控比较变得可行。这种比较将定量地提供微生物对周围介质的机械响应。这一理解也为我们提供了一个严格的方法来探索真正的水动力学效应的游泳微生物。这个奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的知识价值和更广泛的影响审查标准。

项目成果

Geometric effects induce anomalous size-dependent active transport in structured environments

• DOI: 10.1103/physrevfluids.7.l071101
• 发表时间: 2022-07-11
• 期刊: PHYSICAL REVIEW FLUIDS
• 影响因子: 2.7
• 作者: Chopra, Pooja;Quint, David;Liu, Bin
• 通讯作者: Liu, Bin