Diamagnetic Particle Deflection in Ferrofluid Flows through a Rectangular Microchannel
Abstract
Magnetic field-induced particle manipulation is a promising technique for biomicrofluidics applications and offers several advantages over other traditional approaches based on electric, acoustic and optical forces. We present in this talk a fundamental study of diamagnetic particle motion in ferrofluid flows through a rectangular microchannel with a nearby permanent magnet. Due to their negligible magnetization relative to the ferrofluid, diamagnetic particles experience negative magnetophoresis and are repelled away from the magnet. The result is a three-dimensionally focused particle stream flowing near the bottom outer corner of the microchannel. The effects of particle size and position, ferrofluid flow rate and concentration, and magnet-channel distance on the diamagnetic particle deflection are systematically studied. The obtained experimental results agree reasonably with the predictions of a developed three-dimensional analytical model.
- Publication:
-
APS Division of Fluid Dynamics Meeting Abstracts
- Pub Date:
- November 2011
- Bibcode:
- 2011APS..DFDH18009L