Force driven separation of drops by deterministic lateral displacement
Force driven separation of drops by deterministic lateral displacement
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DOI：
10.1039/c2lc40234c
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发表时间：
2012-01-01
期刊：
影响因子：
6.1
通讯作者：
Drazer, German
中科院分区：
文献类型：
--
作者：
Bowman, Timothy;Frechette, Joelle;Drazer, German
我们研究了力驱动确定性横向位移（f-DLD）中液滴的分离，这是微流体中一种有前途的高通量连续分离方法。我们进行了按比例放大的宏观实验，在实验中，水滴落在一排方形的圆柱形障碍物中。这些实验证明了f-DLD的分离能力，并为多种尺寸的液滴的设计提供了见解，包括比圆柱体之间的间隙更大的液滴，当它们通过阵列时表现出明显的变形。我们表明，对于相对于障碍物阵列的驱动力的任何方向，液滴的轨迹都遵循晶格中选定的锁定方向。我们还发现，一个简单的碰撞模型准确地描述了在这里调查的整个尺寸范围内以及所有强制方向的滴的平均迁移角度。此外，我们发现最小和最大水滴首先穿过阵列中障碍物（列）的临界角之间存在大约20度的差异，就该方法的潜在尺寸分辨率而言，这是一个有希望的结果。最后，我们证明了单线的圆柱形障碍物旋转相对于驱动力是能够执行二元分离。单线实验得到的临界角与全阵列实验得到的临界角一致，从而验证了从单个障碍物-落点碰撞中计算落点轨迹（和平均迁移角）的假设。
We investigate the separation of drops in force-driven deterministic lateral displacement (f-DLD), a promising high-throughput continuous separation method in microfluidics. We perform scaled-up macroscopic experiments in which drops settle through a square array of cylindrical obstacles. These experiments demonstrate the separation capabilities-and provide insight for the design-of f-DLD for drops of multiple sizes, including drops that are larger than the gaps between cylinders and exhibit substantial deformation as they move through the array. We show that for any orientation of the driving force relative to the array of obstacles, the trajectories of the drops follow selected locking directions in the lattice. We also found that a simple collision model accurately describes the average migration angles of the drops for the entire range of sizes investigated here, and for all forcing directions. In addition, we found a difference of approximately 20 degrees between the critical angles at which the smallest and largest drops first move across a line of obstacles (column) in the array, a promising result in terms of potential size resolution of this method. Finally, we demonstrate that a single line of cylindrical obstacles rotated with respect to the driving force is capable of performing binary separations. The critical angles obtained in such single line experiments, moreover, agree with those obtained using the full array, thus validating the assumption in which the trajectory (and average migration angle) of the drops is calculated from individual obstacle-drop collisions.