Analytical and Bioanalytical Chemistry

, Volume 396, Issue 2, pp 707–714 | Cite as

Magnetic-based purification system with simultaneous sample washing and concentration

  • Qasem RamadanEmail author
  • Ting Ting Lau
  • Shihan Bryan Ho
Original Paper


Simultaneous washing and concentration of magnetic microparticles was demonstrated using a rotational magnetic system under a continuous-flow condition. The rotation of periodically arranged permanent magnets close to a fluidic channel carrying a suspension of magnetic particles allows the trapping and releasing of particles along the fluidic channel in a periodic manner. Each trapping and releasing event resembles one washing cycle in conventional biological assays. Concentration efficiencies of 99.75 ± 0.083% at a flow rate of 200 µl/min and 88.10 ± 3.17% at a flow rate of 1,000 µl/min and a purification efficiency of 99.10 ± 4.3% at a flow rate of 900 µl/min were achieved.


Continuous flow Washing Separation Magnetic particles 



This research was supported by A star-Exploit Technologies (ETPL) under Flagship grant no. F07/E/013. The authors thank ETPL and the Institute of Microelectronics for their support.

Supplementary material

216_2009_3276_MOESM1_ESM.doc (1.3 mb)
ESM 1 (DOC 1301 kb)

(WMV 2185 kb)


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Qasem Ramadan
    • 1
    • 4
    Email author
  • Ting Ting Lau
    • 2
  • Shihan Bryan Ho
    • 3
  1. 1.Bioelectronics Program, Institute of MicroelectronicsSingaporeRepublic of Singapore
  2. 2.Nanyang Technological UniversitySingaporeRepublic of Singapore
  3. 3.Department of Biomedical EngineeringNational University of SingaporeSingaporeRepublic of Singapore
  4. 4.Swiss Federal Institute of Technology (EPFL), Laboratory of MicrosystemsLausanneSwitzerland

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