Microfluidics and Nanofluidics

, Volume 17, Issue 6, pp 973–982 | Cite as

Combining positive and negative magnetophoreses to separate particles of different magnetic properties

  • Taotao Zhu
  • Rui Cheng
  • Yufei Liu
  • Jian He
  • Leidong Mao
Research Paper


A new separation method that combines both positive and negative magnetophoreses based on ferrofluids is used to separate mixtures of particles with different magnetic properties. Ferrofluids are stable magnetic nanoparticles suspensions. Under external magnetic field gradients, particles with a larger magnetization within the ferrofluids are attracted to a magnet while the ones with a smaller magnetization are pushed away from it. Based on this principle, we report the design, modeling, fabrication, and characterization of the separation device and use it to separate magnetic and non-magnetic particles, as well as particles with different magnetizations. This scheme is simple, cost-effective, and label-free compared to other existing techniques.


Separation Ferrofluid Microfluidics Magnetophoresis 



Research reported in this publication was supported by the National Institute of General Medical Sciences of the National Institutes of Health under Award Number R21GM104528. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Taotao Zhu
    • 1
  • Rui Cheng
    • 2
  • Yufei Liu
    • 3
  • Jian He
    • 3
  • Leidong Mao
    • 2
  1. 1.Department of Chemistry, Nanoscale Science and Engineering CenterThe University of GeorgiaAthensUSA
  2. 2.College of Engineering, Nanoscale Science and Engineering CenterThe University of GeorgiaAthensUSA
  3. 3.Department of Physics and AstronomyClemson UniversityClemsonUSA

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