Magnetic-based purification system with simultaneous sample washing and concentration


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.

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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.

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Correspondence to Qasem Ramadan.

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Ramadan, Q., Lau, T.T. & Ho, S.B. Magnetic-based purification system with simultaneous sample washing and concentration. Anal Bioanal Chem 396, 707–714 (2010) doi:10.1007/s00216-009-3276-9

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  • Continuous flow
  • Washing
  • Separation
  • Magnetic particles