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Flow-orthogonal bead oscillation in a microfluidic chip with a magnetic anisotropic flux-guide array.

ABSTRACT: A new concept for the manipulation of superparamagnetic beads inside a microfluidic chip is presented in this paper. The concept allows for bead actuation orthogonal to the flow direction inside a microchannel. Basic manipulation functionalities were studied by means of finite element simulations and results were oval-shaped steady state oscillations with bead velocities up to 500 μm/s. The width of the trajectory could be controlled by prescribing external field rotation. Successful verification experiments were performed on a prototype chip fabricated with excimer laser ablation in polycarbonate and electroforming of nickel flux-guides. Bead velocities up to 450 μm/s were measured in a 75 μm wide channel. By prescribing the currents in the external quadrupole magnet, the shape of the bead trajectory could be controlled.

SUBMITTER: van Pelt S

PROVIDER: S-EPMC3051104 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Flow-orthogonal bead oscillation in a microfluidic chip with a magnetic anisotropic flux-guide array.

van Pelt Stijn S Derks Roy R Matteucci Marco M Hansen Mikkel Fougt MF Dietzel Andreas A

Biomedical microdevices 20110401 2

A new concept for the manipulation of superparamagnetic beads inside a microfluidic chip is presented in this paper. The concept allows for bead actuation orthogonal to the flow direction inside a microchannel. Basic manipulation functionalities were studied by means of finite element simulations and results were oval-shaped steady state oscillations with bead velocities up to 500 μm/s. The width of the trajectory could be controlled by prescribing external field rotation. Successful verificatio ...[more]

PMID: 21165700

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