Chien Wei, Zhang Zunmin, Gompper Gerhard, Fedosov Dmitry A
Theoretical Soft Matter and Biophysics, Institute of Complex Systems and Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany.
Biomicrofluidics. 2019 Jul 26;13(4):044106. doi: 10.1063/1.5112033. eCollection 2019 Jul.
Deterministic lateral displacement (DLD) microfluidic devices promise versatile and precise processing of biological samples. However, this prospect has been realized so far only for rigid spherical particles and remains limited for biological cells due to the complexity of cell dynamics and deformation in microfluidic flow. We employ mesoscopic hydrodynamics simulations of red blood cells (RBCs) in DLD devices with circular posts to better understand the interplay between cell behavior in complex microfluidic flow and sorting capabilities of such devices. We construct a mode diagram of RBC behavior (e.g., displacement, zig-zagging, and intermediate modes) and identify several regimes of RBC dynamics (e.g., tumbling, tank-treading, and trilobe motion). Furthermore, we link the complex interaction dynamics of RBCs with the post to their effective cell size and discuss relevant physical mechanisms governing the dynamic cell states. In conclusion, sorting of RBCs in DLD devices based on their shear elasticity is, in general, possible but requires fine-tuning of flow conditions to targeted mechanical properties of the RBCs.
确定性侧向位移（DLD）微流控设备有望对生物样品进行多功能且精确的处理。然而，到目前为止，这一前景仅在刚性球形颗粒上得以实现，由于微流控流动中细胞动力学和变形的复杂性，对于生物细胞而言仍受到限制。我们采用介观流体动力学模拟红细胞（RBC）在带有圆形柱体的DLD设备中的情况，以更好地理解复杂微流控流动中细胞行为与此类设备分选能力之间的相互作用。我们构建了红细胞行为的模式图（例如位移、曲折运动和中间模式），并识别出红细胞动力学的几种状态（例如翻滚、坦克履带式运动和三叶运动）。此外，我们将红细胞与柱体之间复杂的相互作用动力学与其有效细胞大小联系起来，并讨论控制动态细胞状态的相关物理机制。总之，基于红细胞的剪切弹性在DLD设备中对其进行分选通常是可行的，但需要针对红细胞的目标力学性质对流动条件进行微调。
