Flow-induced clustering and alignment of vesicles and red blood cells in microcapillaries
Flow-induced clustering and alignment of vesicles and red blood cells in microcapillaries
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DOI：
10.1073/pnas.0811484106
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发表时间：
2009-04-14
影响因子：
11.1
通讯作者：
Gompper, Gerhard
中科院分区：
文献类型：
--
作者：
McWhirter, J. Liam;Noguchi, Hiroshi;Gompper, Gerhard
微流体装置的最新发展允许对单个液体微滴、胶囊和细胞进行研究和操纵。几个红细胞（RBC）或微胶囊在狭窄毛细管中的集体行为决定了它们的流动诱导形态，排列和有效粘度。这里的基本利益是这些对象的流动行为和弹性和变形能力，它们在微通道中的远程流体动力学相互作用，和热膜波动之间的关系。我们研究这些机制在硅片模型，它结合了基于粒子的中尺度模拟技术的流体动力学与三角形膜模型。2个基本控制参数是RBC的体积分数（试管红细胞压积，H-T）和流速。我们的模拟表明，已经在非常低的H-T，红细胞的变形性意味着一个流动诱导的集群形成以上的阈值流速。在较高的H-T值，我们预测3个不同的阶段：一个由无序的双凹盘形红细胞，另一个与降落伞形红细胞排列在一个文件，和第三个拖鞋形红细胞排列为2个平行交叉的行。变形介导的聚集以及红细胞和微胶囊的排列与物理学、生物学和医学中的许多潜在应用相关，例如血液诊断和微流体装置中的细胞分选。
The recent development of microfluidic devices allows the investigation and manipulation of individual liquid microdroplets, capsules, and cells. The collective behavior of several red blood cells (RBCs) or microcapsules in narrow capillaries determines their flow-induced morphology, arrangement, and effective viscosity. Of fundamental interest here is the relation between the flow behavior and the elasticity and deformability of these objects, their long-range hydrodynamic interactions in microchannels, and thermal membrane undulations. We study these mechanisms in an in silico model, which combines a particle-based mesoscale simulation technique for the fluid hydrodynamics with a triangulated-membrane model. The 2 essential control parameters are the volume fraction of RBCs (the tube hematocrit, H-T), and the flow velocity. Our simulations show that already at very low H-T, the deformability of RBCs implies a flow-induced cluster formation above a threshold flow velocity. At higher H-T values, we predict 3 distinct phases: one consisting of disordered biconcave-disk-shaped RBCs, another with parachute-shaped RBCs aligned in a single file, and a third with slipper-shaped RBCs arranged as 2 parallel interdigitated rows. The deformation-mediated clustering and the arrangements of RBCs and microcapsules are relevant for many potential applications in physics, biology, and medicine, such as blood diagnosis and cell sorting in microfluidic devices.