In this work, we report a microfluidics-based approach to the sorting of two-particle and three-particle mixtures using a micropillar arrangement. Using a simple retain-and-release strategy, we demonstrate the capability of the device to completely sort two-particle mixtures containing particles at various ratios. Additionally, for three-particle mixture, we demonstrate enrichment and recovery of largest size particles and generation of streams completely free of the largest particles. The efficiency of the sorting process is characterized in terms of purity and recovery using Fluorescence Activated Cell Sorting (FACS). We report high purity and recovery of the target particles for all the particle ratios investigated and the particle release strategy employed here is observed to be crucial to this. Through a systematic investigation on the effect of particle ratios on the sorting process, the present work demonstrates the ability of pillar-based microfluidic devices to sort microparticles in diverse applications, beyond the usual blood cell sorting application.

在这项工作中，我们报告了一种基于微流体的方法，使用微柱排列对两颗粒和三颗粒混合物进行分类。使用简单的保留和释放策略，我们证明了该设备能够完全分选包含不同比例颗粒的两颗粒混合物的功能。此外，对于三颗粒混合物，我们证明了最大尺寸颗粒的富集和回收以及完全不含最大颗粒的流的产生。分选过程的效率通过使用荧光激活细胞分选（FACS）的纯度和回收率来表征。我们报告了所研究的所有颗粒比率的高纯度和目标颗粒的回收率，并且观察到此处采用的颗粒释放策略对此至关重要。