微通道磁泳分离系统中微粒的运动特性及分离效率研究  

Study on the Particle Motion Behavior and Separation Efficiency in Microchannels of the Magnetophoretic Separation System

作　　者：韦卫中[1] 曹全梁[2] 冯洋[2] 韩小涛[2] 

机构地区：[1]华中科技大学同济医学院附属武汉市妇女儿童医疗保健中心,武汉430016 [2]华中科技大学国家脉冲强磁场科学中心,武汉430074

出　　处：《中国生物医学工程学报》2015年第1期17-23,共7页Chinese Journal of Biomedical Engineering

基　　金：教育部新世纪优秀人才支持计划(NCET-13-0225);国家自然科学基金(51407083,51077064)

摘　　要：通过磁场力诱导微/纳米微粒定向移动实现分离的磁泳分离技术在生化分离及检测等领域得到了广泛关注,其在微流控系统中的应用及微尺度下的分离特性成为目前研究的热点。基于磁泳分离系统中磁性微粒的受力和运动方程,建立梯度磁场和流场共同作用下磁性微粒的二维动力学数值模型,对不同流速条件和管道结构下微管道内单/双磁性微粒的动力学特性和分离行为进行数值研究。研究表明:T型管道内不同流层的宽度可由入口流速比来调控,当流速比从1增加至6时,磁性微粒所在的流层宽度从100μm减小为53μm,大大降低不同微粒间的初始间距,可有效提高微粒群间的分离识别度;当不同粒子群间完全分离后,在微管道出口处引入扩张通道,可将微粒群间的分离间距从5.4μm提高至26.8μm。在此基础上,实现粒径2和3μm磁性微粒的有效分离。研究结果对于提高磁泳分离效率和优化微流控系统具有理论指导意义。Magnetophoretic separation technology by use of magnetic forces on the micro/nano particles for transporting and separating has attracted wide attention in the fields of biochemical separation and detection. Its applications in microfluidics with corresponding studies of separation behavior in micro-scale have been one hot issue in the research field. Based on the equations of forces acting on the particles and motion behavior, this paper established a two dimensional dynamical numerical model for particles under the action of gradient magnetic field and flow field. Then the motion behavior and separation efficiency of particles with single/double sizes were investigated for different flow rates and microchannel structures. Studies have shown that ： 1 ） Widths of the two fluid streams flowing in the T-shaped microchannel can be controlled by adjusting the flow rate ratio of the two inlets. The width of the stream containing particles can be decreased from 100 μm to 53 μm when the inlet flow rate ratio changes from 1 to 6, which has greatly decreased the initial distances between partilces and could be used to improve the separation resolution. 2） When the two types of magnetic particles have been separated completely, the spacing distance between fully separated particles can be greatly amplified from 5.4 μm to 26.8 μm by introducing a broadened segment along the channel outlet. Then it has been demonstrated to realize the separation of 2 μm and 3 μm particles. These results should have a theoretical significance toenhance the magnetophoretic separation efficiency and optimize the microfluidic system.

关 键 词：磁泳分离 微流控 分离效率 磁性微粒 

分 类 号：R318[医药卫生—生物医学工程]