Green James V, Kniazeva Tatiana, Abedi Mehdi, Sokhey Darshan S, Taslim Mohammad E, Murthy Shashi K
Department of Chemical Engineering, Northeastern University, 360 Huntington Ave. 342 SN, Boston, Massachusetts 02115, USA.
Lab Chip. 2009 Mar 7;9(5):677-85. doi: 10.1039/b813516a. Epub 2008 Nov 21.
Microfluidic channels coated with ligands are a versatile platform for the separation or enrichment of cells from small sample volumes. This adhesion-based mode of separation is mediated by ligand-receptor bonds between the cells and channel surface and also by fluid shear stress. This paper demonstrates how aspects of microchannel geometry can play an additional role in controlling cell adhesion. With a combination of computational fluid dynamics modeling and cell adhesion experiments, channels with sharp turns are shown to have regions with near-zero velocity at the turn regions where large numbers of cells adhere or become collected. The lack of uniform adhesion in the turn regions compared to other regions of these channels, together with the large variability in observed cell adhesion indicates that channels with sharp turns are not optimal for cell-capture applications where predictable cell adhesion is desired. Channels with curved turns, on the other hand are shown to provide more uniform and predictable cell adhesion provided the gap between parallel arms of the channels is sufficiently wide. The magnitude of cell adhesion in these curved channels is comparable to that in straight channels with no turns.
涂有配体的微流体通道是从小样本体积中分离或富集细胞的通用平台。这种基于粘附的分离模式由细胞与通道表面之间的配体 - 受体键以及流体剪切应力介导。本文展示了微通道几何形状的各个方面如何在控制细胞粘附中发挥额外作用。通过计算流体动力学建模和细胞粘附实验相结合，发现带有急转弯的通道在转弯区域具有接近零速度的区域，大量细胞在此处粘附或聚集。与这些通道的其他区域相比，转弯区域缺乏均匀的粘附，并且观察到的细胞粘附存在很大变异性，这表明对于需要可预测细胞粘附的细胞捕获应用而言，带有急转弯的通道并非最佳选择。另一方面，结果表明只要通道平行臂之间的间隙足够宽，带有弯曲转弯的通道就能提供更均匀且可预测的细胞粘附。这些弯曲通道中的细胞粘附程度与无转弯的直通道相当。
