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Microfluidic capturing-dynamics of paramagnetic bead suspensions

Christian Mikkelsen·Henrik Bruus
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Abstract

We study theoretically the capturing of paramagnetic beads by a magnetic field gradient in a microfluidic channel treating the beads as a continuum. Bead motion is affected by both fluidic and magnetic forces. The transfer of momentum from beads to the fluid creates an effective bead-bead interaction that greatly aids capturing. We demonstrate that for a given inlet flow speed a critical density of beads exists above which complete capturing takes place.

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Christian Mikkelsen, Henrik Bruus. 2005-05-06. Microfluidic capturing-dynamics of paramagnetic bead suspensions. https://doi.org/10.1039/b507104f

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