Liquid recirculation in microfluidic channels by the interplay of capillary and centrifugal forces
Liquid recirculation in microfluidic channels by the interplay of capillary and centrifugal forces
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DOI：
10.1007/s10404-010-0585-4
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发表时间：
2010-10-01
影响因子：
2.8
通讯作者：
Ricco, Antonio J.
中科院分区：
文献类型：
--
作者：
Garcia-Cordero, Jose L.;Basabe-Desmonts, Lourdes;Ricco, Antonio J.
我们展示了一种在微流控通道中循环液体的技术，通过离心力和毛细管力的交替作用，使液体样品的整个体积迅速达到表面的一个扩散长度(增量)内，即使样品体积是增量和几何器件面积的数百倍。这是通过重复、随机地采样盘上样品储存库以在微通道中形成厚度增量的薄流体层来实现的，在扩散时间内保持接触，然后通过盘片旋转和停止快速地将流体层交换为新鲜的等分。利用这种技术，只要具有最大表面积的通道壁是亲水性的，就可以在许多尺寸的微流体通道中处理从微升到毫升的液体体积。提出了描述装置内离心力和毛细管力平衡的理论模型，并对模型进行了实验验证。
We demonstrate a technique to recirculate liquids in a microfluidic channel by alternating predominance of centrifugal and capillary forces to rapidly bring the entire volume of a liquid sample to within one diffusion length, delta, of the surface, even for sample volumes hundreds of times the product of delta and the geometric device area. This is accomplished by repetitive, random sampling of an on-disc sample reservoir to form a thin fluid layer of thickness delta in a microchannel, maintaining contact for the diffusion time, then rapidly exchanging the fluid layer for a fresh aliquot by disc rotation and stoppage. With this technique, liquid volumes of microlitres to millilitres can be handled in many sizes of microfluidic channels, provided the channel wall with greatest surface area is hydrophilic. We present a theoretical model describing the balance of centrifugal and capillary forces in the device and validate the model experimentally.