Quantitative characterization of magnetic separators: comparison of systems with and without integrated microfluidic mixers.
We present two new types of microfluidic passive magnetic bead separator systems as well as methods for performing quantitative characterizations of them. Both systems consist of a microfluidic channel with long rectangular magnetic elements of permalloy that are placed by the sides of the channel and magnetized by an external magnetic field. In one of the systems, a staggered herringbone microfluidic mixer is integrated in the channel. The characterization of the systems includes magnetic measurements of the capture-and-release efficiencies, estimates of distributions of captured beads in a channel from micrographs, and simulations and analytical models of bead trajectories, capture efficiencies, and capture distributions. We show that the efficiencies of both systems compare favorably to those in the literature. For the studied geometries, the mixer is demonstrated to increase the bead capture-and-release efficiency for a fixed flow rate by up to a factor of two. Moreover, high capture efficiencies can be achieved in the system with mixer at up to ten times higher flow rates than in the system without mixer.
Lund-Olesen
Torsten
T
MIC-Department of Micro and Nanotechnology, DTU, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark. tlo@mic.dtu.dk
Bruus
Henrik
H
Hansen
Mikkel Fougt
MF
D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D018189:Immunomagnetic Separation / Q000295:instrumentation* / Q000379:methods; D008280:Magnetics / Q000295:instrumentation*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods; D008962:Models, Theoretical; D018511:Systems Integration