Chen Hsiu-Hung, Sun Bingbing, Tran Kenny K, Shen Hong, Gao Dayong
Department of Mechanical Engineering, University of Washington, Seattle, WA 98195, USA.
J Biomech Eng. 2009 Jul;131(7):074505. doi: 10.1115/1.3127258.
Grooved structures have been widely studied in particle separation and fluid mixing in microfluidic channel systems. In this brief report, we demonstrate the use of patterning flows produced by two different sorts of grooved surfaces: single slanted groove series (for enrichment patterns) and V-shaped groove series (for focusing patterns), into a microfluidic device to continuously manipulate the flowing particles, including microbeads with 6 microm, 10 microm, and 20 microm in diameter and mouse dendritic cells of comparable sizes to the depth of the channel. The device with grooved channels was developed and fabricated by soft-lithographic techniques. The particle distributions after passing through the single slanted grooves illustrate the size-dependent enrichment profiles. On the other hand, particles passing through the V-shaped grooves show focusing patterns downstream, for the combination effect from both sides of single slanted grooves setup side-by-side. Compared with devices utilizing sheath flows, the focusing patterns generated in this report are unique without introducing additional flow control. The alignment of the concentrated particles is expected to facilitate the visualization of sizing and counting in cell-based devices. On the other hand, the size-dependent patterns of particle distributions have the potential for the application of size-based separation.
在微流控通道系统中，沟槽结构已被广泛应用于颗粒分离和流体混合研究。在本简要报告中，我们展示了如何将由两种不同类型的沟槽表面（单倾斜沟槽系列（用于富集模式）和V形沟槽系列（用于聚焦模式））产生的图案化流引入微流控装置，以连续操纵流动的颗粒，包括直径为6微米、10微米和20微米的微珠以及尺寸与通道深度相当的小鼠树突状细胞。带有沟槽通道的装置是通过软光刻技术开发和制造的。通过单倾斜沟槽后的颗粒分布说明了尺寸依赖性富集曲线。另一方面，通过V形沟槽的颗粒在下游呈现聚焦模式，这是由于并排设置的单倾斜沟槽两侧的组合效应。与利用鞘流的装置相比，本报告中产生的聚焦模式是独特的，无需引入额外的流量控制。预计浓缩颗粒的排列将有助于基于细胞的装置中尺寸测量和计数的可视化。另一方面，颗粒分布的尺寸依赖性模式具有基于尺寸分离应用的潜力。
