School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, P. R. China.
School of Biomedical Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, P. R. China.
Electrophoresis. 2020 Jun;41(10-11):909-916. doi: 10.1002/elps.202000002. Epub 2020 Mar 19.
In the present study, we numerically demonstrate an approach for separation of micro and sub-micro diamagnetic particles in dual ferrofluid streams based on negative magnetophoresis. The dual streams are constructed by an intermediate sheath flow, after which the negative magnetophoretic force induced by an array of permanent magnets dominates the separation of diamagnetic particles. A simple and efficient numerical model is developed to calculate the motions of particles under the action of magnetic field and flow field. Effects of the average flow velocity, the ratio of sheath fluid flow to sample fluid flow, the number of the magnet pair as well as the position of magnet pair are investigated. The optimal parametric condition for complete separation is obtained through the parametric analysis, and the separation principle is further elucidated by the force analysis. The separation of smaller micro and sub-micro diamagnetic particles is finally demonstrated. This study provides an insight into the negative magnetophoretic phenomenon and guides the fabrication of feasible, low-cost diagnostic devices for sub-micro particle separation.
在本研究中，我们通过数值模拟展示了一种基于负磁泳现象分离双铁磁流中微米和亚微米级顺磁颗粒的方法。双铁磁流通过中间鞘流构建，随后由永磁体阵列产生的负磁泳力主导顺磁颗粒的分离。我们开发了一种简单而高效的数值模型，以计算颗粒在磁场和流场作用下的运动。研究了平均流速、鞘流与样品流的比例、磁对数量以及磁对位置对颗粒运动的影响。通过参数分析得到了完全分离的最佳参数条件，并通过受力分析进一步阐明了分离原理。最后，演示了对较小的微米和亚微米级顺磁颗粒的分离。本研究深入了解了负磁泳现象，并为亚微米级颗粒分离的可行、低成本诊断设备的制造提供了指导。
