Interfacial tension based on-chip extraction of microparticles confined in microfluidic Stokes flows
Interfacial tension based on-chip extraction of microparticles confined in microfluidic Stokes flows
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DOI：
10.1063/1.4898040
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发表时间：
2014-10-06
影响因子：
4
通讯作者：
He, Xiaoming
中科院分区：
文献类型：
--
作者：
Huang, Haishui;He, Xiaoming
涉及两种不混溶流体（油和水）的微流体已经越来越多地用于生产具有广泛应用的水凝胶微粒。然而，难以从雷诺数（惯性与粘性力的比率）远小于1的油的微流体斯托克斯流中提取微粒，其中主导粘性力倾向于驱动微粒与周围的油一起移动。在这里，我们提出了一种被动的方法提取水凝胶微粒在微流控斯托克斯流从油到水提取液的芯片上，通过利用油和微粒之间的固有界面张力。我们进一步揭示了一个“扩展的限制层”的石油和水提取溶液之间的界面旁边的厚度必须小于有效提取微粒的半径。该方法使用简单的平面合并微通道设计，其可以容易地制造并进一步集成到流体系统中以提取微粒用于广泛的应用。(C)2014 AIP出版有限责任公司。
Microfluidics involving two immiscible fluids (oil and water) has been increasingly used to produce hydrogel microparticles with wide applications. However, it is difficult to extract the microparticles out of the microfluidic Stokes flows of oil that have a Reynolds number (the ratio of inertia to viscous force) much less than one, where the dominant viscous force tends to drive the microparticles to move together with the surrounding oil. Here, we present a passive method for extracting hydrogel microparticles in microfluidic Stokes flow from oil into aqueous extracting solution on-chip by utilizing the intrinsic interfacial tension between oil and the microparticles. We further reveal that the thickness of an "extended confining layer" of oil next to the interface between oil and aqueous extracting solution must be smaller than the radius of microparticles for effective extraction. This method uses a simple planar merging microchannel design that can be readily fabricated and further integrated into a fluidic system to extract microparticles for wide applications. (C) 2014 AIP Publishing LLC.