Separation of microparticle in viscoelastic fluid is highly required in the field of biology and clinical medicine. For instance, the separation of the target cell from blood is an important prerequisite step for the drug screening and design. The microfluidic device is an efficient way to achieve the separation of the microparticle in the viscoelastic fluid. However, the existing microfluidic methods often have some limitations, including the requirement of the long channel length, the labeling process, and the low throughput. In this work, based on the elastic-inertial effect in the viscoelastic fluid, a new separation method is proposed where a gradually contracted microchannel is designed to efficiently adjust the forces exerted on the particle, eventually achieving the high-efficiency separation of different sized particles in a short channel length and at a high throughput. In addition, the separation of WBCs and RBCs is also validated in the present device. The effect of the flow rate, the fluid property, and the channel geometry on the particle separation is systematically investigated by the experiment. With the advantage of small footprint, simple structure, high throughput, and high efficiency, the present microfluidic device could be utilized in the biological and clinical fields, such as the cell analysis and disease diagnosis.

中文翻译：

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逐渐收缩的微通道中微粒的弹性惯性分离

粘弹性流体中微粒的分离是生物学和临床医学领域的迫切需求。例如，从血液中分离靶细胞是药物筛选和设计的重要先决步骤。微流控装置是实现粘弹性流体中微粒分离的有效途径。然而，现有的微流控方法往往存在一些局限性，包括长通道长度的要求、标记过程和低通量。在这项工作中，基于粘弹性流体中的弹性惯性效应，提出了一种新的分离方法，其中设计了逐渐收缩的微通道以有效调节施加在颗粒上的力，最终实现了在短通道长度和高通量下对不同尺寸颗粒的高效分离。此外，白细胞和红细胞的分离也在本装置中得到验证。通过实验系统地研究了流速、流体性质和通道几何形状对颗粒分离的影响。凭借占地面积小、结构简单、高通量和高效率的优势，本微流控装置可用于细胞分析和疾病诊断等生物和临床领域。并通过实验系统研究了通道几何形状对颗粒分离的影响。凭借占地面积小、结构简单、高通量和高效率的优势，本微流控装置可用于细胞分析和疾病诊断等生物和临床领域。并通过实验系统研究了通道几何形状对颗粒分离的影响。凭借占地面积小、结构简单、高通量和高效率的优势，本微流控装置可用于细胞分析和疾病诊断等生物和临床领域。