Department of Mechanical and Aerospace Engineering, New York University Tandon School of Engineering, Brooklyn, NY 11201, USA.
Soft Matter. 2016 Dec 21;13(1):37-48. doi: 10.1039/c6sm01879c.
The transport of suspensions of microparticles in confined environments is associated with complex phenomena at the interface of fluid mechanics and soft matter. Indeed, the deposition and assembly of particles under flow involve hydrodynamic, steric and colloidal forces, and can lead to the clogging of microchannels. The formation of clogs dramatically alters the performance of both natural and engineered systems, effectively limiting the use of microfluidic technology. While the fouling of porous filters has been studied at the macroscopic level, it is only recently that the formation of clogs has been considered at the pore-scale, using microfluidic devices. In this review, we present the clogging mechanisms recently reported for suspension flows of colloidal particles and for biofluids in microfluidic channels, including sieving, bridging and aggregation of particles. We discuss the technological implications of the clogging of microchannels and the schemes that leverage the formation of clogs. We finally consider some of the outstanding challenges involving clogging in human health, which could be tackled with microfluidic methods.
在受限环境中悬浮微粒子的输送与流体力学和软物质界面的复杂现象有关。事实上，在流动下的粒子沉积和组装涉及流体动力、空间和胶体力，并可能导致微通道堵塞。堵塞的形成极大地改变了自然和工程系统的性能，有效地限制了微流控技术的应用。虽然多孔过滤器的堵塞在宏观层面上已经得到了研究，但直到最近，在使用微流控装置时，才开始在孔隙尺度上考虑堵塞的形成。在这篇综述中，我们介绍了最近报道的用于胶体颗粒悬浮液和微流道中生物流体的堵塞机制，包括粒子的筛分、桥接和聚集。我们讨论了微通道堵塞的技术意义以及利用堵塞形成的方案。最后，我们考虑了一些涉及人类健康中堵塞的突出挑战，这些挑战可以通过微流控方法来解决。
