Simultaneous sample washing and concentration using a “trapping-and-releasing” mechanism of magnetic beads on a microfluidic chip

Simultaneous washing and concentration of functionalized magnetic beads in a complex sample solution was demonstrated by applying a rotational magnetic actuation system to a microfluidic chip under continuous flow conditions. The rotation of periodically arranged small permanent magnets close to the fluidic channel carrying a magnetic bead suspension allows trapping and releasing of the beads along the fluidic channel in a periodical manner. Each trapping and releasing event resembles one washing cycle.