Jiang Di, Ni Chen, Tang Wenlai, Huang Di, Xiang Nan
College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China.
School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China.
Biomicrofluidics. 2021 Jul 2;15(4):041501. doi: 10.1063/5.0058732. eCollection 2021 Jul.
Inertial microfluidics has brought enormous changes in the conventional cell/particle detection process and now become the main trend of sample pretreatment with outstanding throughput, low cost, and simple control method. However, inertial microfluidics in a straight microchannel is not enough to provide high efficiency and satisfying performance for cell/particle separation. A contraction-expansion microchannel is a widely used and multifunctional channel pattern involving inertial microfluidics, secondary flow, and the vortex in the chamber. The strengthened inertial microfluidics can help us to focus particles with a shorter channel length and less processing time. Both the vortex in the chamber and the secondary flow in the main channel can trap the target particles or separate particles based on their sizes more precisely. The contraction-expansion microchannels are also capable of combining with a curved, spiral, or serpentine channel to further improve the separation performance. Some recent studies have focused on the viscoelastic fluid that utilizes both elastic forces and inertial forces to separate different size particles precisely with a relatively low flow rate for the vulnerable cells. This article comprehensively reviews various contraction-expansion microchannels with Newtonian and viscoelastic fluids for particle focusing, separation, and microfluid mixing and provides particle manipulation performance data analysis for the contraction-expansion microchannel design.
惯性微流控技术给传统的细胞/颗粒检测过程带来了巨大变革,如今已凭借出色的通量、低成本以及简单的控制方法成为样品预处理的主流趋势。然而,直微通道中的惯性微流控技术在细胞/颗粒分离方面尚不足以提供高效且令人满意的性能。收缩-扩张微通道是一种广泛应用的多功能通道模式,涉及惯性微流控、二次流以及腔室内的涡流。强化的惯性微流控技术能够帮助我们在更短的通道长度和更少的处理时间内实现颗粒聚焦。腔室内的涡流和主通道中的二次流都能够捕获目标颗粒或更精确地根据颗粒大小进行分离。收缩-扩张微通道还能够与弯曲、螺旋或蛇形通道相结合,进一步提升分离性能。近期的一些研究聚焦于粘弹性流体,这种流体利用弹力和惯性力在相对较低的流速下精确分离不同大小的颗粒,适用于脆弱细胞。本文全面综述了用于颗粒聚焦、分离和微流体混合的牛顿流体和粘弹性流体的各种收缩-扩张微通道,并为收缩-扩张微通道设计提供颗粒操控性能数据分析。