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.

在小几何形状或微流体中，精确控制流体流量，已被用作控制或运输小颗粒的强大手段。微流体可以可能用于操纵微生物，以研究它们如何感知环境的机械性能（机械敏化）。对这些微生物的机制有充分的了解可能会导致其行为的机械控制，以替代生态，环境和健康应用中传统的化学处理方法。微分化技术的进步已经在微流体设备中产生了增长的几何形状，并且可以使用计算流体动力学预测这些设备内的流量。该项目使用一种称为基于对称性的抽象的技术探讨了与微生物微观流动相关的微流体流的基本原理。为该项目开发的高级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。拟议的努力还由著名的教育组成部分组成，包括“虚拟成像实验室”和“ Kirigami-Origami微流体学”宣传计划，这些计划将互动研究经验带给常规课堂，并实际上是为公众提供的。这种受控的微流体环境将用于隔离微生物对周围培养基的无源机械响应，从主动反应中。这种功能将提高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）开发和实验测量基于对称性的微流体基础，用于高级操纵功能，（ii）将这些功能扩展到无扰动的活细胞操作（通过构建“细菌跑步机”），以及（iii）最终实现通道和像素化的微氧化型应用程序。通过桥接流动模式和流对称性，超出简单几何形状的微流体的更广泛的设计空间可用于先进的微流体应用。通过通过流动对称性从机械扰动中牢固地分离微生物，对无扰动和机械扰动条件下的微生物进行了控制的比较，变得可行。这种比较将定量地为周围培养基提供微生物的机制。这种理解还为我们提供了一种严格的方法来探索游泳微生物的真正流体动力效应。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响评估标准来评估值得支持。

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