Lateral migration of droplets and vesicles in inertial microfluidics

惯性微流体中液滴和囊泡的横向迁移

• 批准号: 1804004
• 负责人: Soojung Hur
• 金额: $ 33.13万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-15 至 2022-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1804004&HistoricalAwards=false
• 关键词: Lateral; migration; droplets; vesicles; inertial

Manipulating and positioning small objects like cells or drops in flow is important in industry, biology, and medicine. The properties of these objects, including size, shape, and softness, often distinguish particles of interest from complex mixtures of many particles. However, current tools for measuring the deformability or softness of such objects are very limited. Often, these tools can analyze objects only slowly and in small numbers, so that large heterogeneous samples cannot be processed efficiently. Alternately, some tools do not allow only objects with certain properties to be selected and collected for further analysis. This study aims to understand how the mechanical properties of cell-like objects affects their behavior in flow in small channels and relate that behavior to the object's properties. Experiments and computer simulations will be used to examine cell-like objects undergoing flow. The results will be used to engineer a rapid, cellular deformability measurement tool that will also allow cell sorting. Such a device would benefit various biological and clinical applications, such as cancer diagnostics, stem cell research, and drug development. This research will identify critical factors that enhance lateral migration of deformable microscale objects and will establish the fundamental understanding required to predict locations of deformable objects with known properties in channel flow. When microscale objects are injected into inertial microfluidics operating at finite particle-Reynolds-number, a balance of opposing, inertial lift forces acting on flowing microscale objects leads to unique lateral and vertical positions in a rectangular microchannel. An additional force also exists away from the channel walls in Poiseuille flow, which locates deformable objects closer to the channel center than rigid ones. By taking particle size into account, the location of objects in the channel can be used to infer their deformability. Also, the inherently high flow speeds at which inertial effects are relevant make inertial microfluidic systems ideal candidates for high-throughput deformability measurements. This study examines behaviors of droplets and vesicles in inertial flow, experimentally and computationally, to explain fundamental aspects of nonlinear particle migration. The experiments span a wide range of parameters and will identify dynamically significant regions of the parameter space, and the simulations will provide non-intrusive access to the flow fields, the balance of forces, and the stability of the flow state.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.

在工业、生物学和医学中，操纵和定位细胞或液滴等小物体非常重要。 这些物体的性质，包括大小、形状和柔软度，通常将感兴趣的颗粒与许多颗粒的复杂混合物区分开来。 然而，目前用于测量这种物体的变形性或柔软度的工具非常有限。 通常，这些工具只能缓慢且少量地分析对象，因此无法有效地处理大型异构样本。 或者，某些工具不允许仅选择和收集具有某些属性的对象以供进一步分析。 本研究旨在了解细胞状物体的力学性质如何影响它们在小通道中的流动行为，并将该行为与物体的性质联系起来。 实验和计算机模拟将被用来检查细胞状物体进行流动。 研究结果将用于设计一种快速的细胞变形性测量工具，该工具也将允许细胞分选。 这样的设备将有利于各种生物和临床应用，如癌症诊断，干细胞研究和药物开发。 这项研究将确定增强可变形微尺度物体横向迁移的关键因素，并将建立预测通道流中具有已知属性的可变形物体位置所需的基本理解。当微尺度物体被注入到以有限颗粒雷诺数操作的惯性微流体中时，作用在流动的微尺度物体上的相反惯性升力的平衡导致矩形微通道中的独特的横向和垂直位置。在Poiffille流中，也存在远离通道壁的附加力，其使可变形物体比刚性物体更靠近通道中心。通过考虑颗粒尺寸，可以使用通道中物体的位置来推断它们的可变形性。此外，惯性效应相关的固有高流速使惯性微流体系统成为高通量变形性测量的理想候选者。本研究探讨惯性流中的液滴和囊泡的行为，实验和计算，解释非线性粒子迁移的基本方面。这些实验涵盖了广泛的参数范围，并将确定参数空间的动态重要区域，模拟将提供对流场、力的平衡和流态稳定性的非侵入性访问。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。