Tapered angle microfluidic device for cell separation using hydrodynamic principle

Abstract

Cell sorting is an essential technique used in a wide range of research, diagnostic, and therapeutic sectors. Fluorescence-activated cell sorting (FACS), magnetic-activated cell sorting (MACS), and CellSearch, which are conventional techniques, possess inherent limitations. For instance, the utilization of EpCam was ineffective in identifying specific malignancies. Cell sorting techniques have undergone significant advancements, with microfluidics being one of them. Regrettably, the current devices suffer from issues such as clogging and necessitate a lengthy main channel. Therefore, the goal of this work is to build and improve a microfluidic device with a tapered angle. There are three designs presented, each with one inlet, at least two exits, one focusing zone, and one tapering region. Using the finite element simulation software COMSOL Multiphysics, two studies are undertaken, the first examining the effect of taper angle on particle separation, and the second analyzing the effect of flow rate on particle separation. Based on the hydrodynamic theory and sedimentation process, this design allows particles to separate. When the taper angle approached 20 degrees, a mixture of 3 μm and 10 μm polystyrene microbeads were successfully separated, and separation continued until the taper angle approached 89 degrees. This technology offers simple, label-free, and continuous separation of many particles in a self-contained device without the use of bulky gear.