A Pneumatic-Control Micro Chip for Microparticle Focusing and Separation Using Inertial Force

• Main Authors: Wei-Chun Ho, 何為竣
• Other Authors: 楊鏡堂
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/46474222775093320528

碩士 === 國立臺灣大學 === 機械工程學研究所 === 105 === In this work, we design a pneumatic-control microfluidic chip based on the theory of inertial focusing to create a single-stream particle flow at the downstream without sheath flow and external forces. The device consists of two stages of focusing channel and an observation zone. The first stage of focusing channel is a high aspect-ratio straight channel which could preliminarily align randomly dispersed particles to two focusing streams due to fluid inertia. The second stage of focusing channel is composed of a special symmetric notch-membrane structure inducing geometry-induced secondary flow to un-stabilize one of the two focusing stream. By inputting pressurized air to one side of lateral membranes, we could adjust the channel geometry in order to control the strength and the direction of secondary flow. Therefore, we can choose either of two focusing streams at the downstream. The observation zone is made up of a slightly divergent channel for decelerating the particles for the convenience of high-speed camera recording. In summary, we present a controllable single-stream device with separation efficiency (the total number of particles divides the difference of number of particles between two exits) as high as 75.6%. We also demonstrate the ability of separating 1 μm particles from 10 μm-1 μm mixture or 5 μm-1 μm mixture which has potential to application for blood separation.