Continuous Particle Sorting Utilizing Cascade Squeeze-Jumping Effect Under Microfluidic Configuration

This paper presents a novel method for continuous particle sorting and collection by using of cascade squeeze-jumping effect under microfluidic configuration. Microparticles with different sizes can be successfully separated at different stages of squeezed sheath flows. Separated microparticles then flow into expansion channel blocks to enlarge the distance of the separated flow streams and are collected at different side channels. Only one high voltage is required for generating all the sheath flows for particle separation by applying a series of variable resister to create different electric field levels such that the system is simple and reliable. This study also adopts numerical simulation to analyze and predict the flow fields and stream lines within the microchannel. Experimental results show that the microchip is capable of continuously separating microparticles with the sizes of 5, 10 and 20 μm using the proposed squeeze-jumping effect. The method proposed in this study provides a simple way to continuously separate microparticles/cells with different sizes. More importantly, no delicate control system and fabrication process are required to achieve the sorting and collection.