Autonomous micro-magnet based systems for highly efficient magnetic separation

Abstract

The various forces experienced by magnetic particles pumped through microfluidic channels placed above a chessboard array of micromagnets were calculated as a function of particle size and device dimensions. A device incorporating magnetically microstructured hard magnetic NdFeB films was fabricated. Good agreement was achieved between the calculated and observed distance over which magnetic particles travel before they are trapped. Using this simple and autonomous device, mixed solutions of magnetic and non-magnetic micro-particles were separated into two distinct solutions containing a concentration of up to 99.9 and 94.5 of non-magnetic and magnetic particles, respectively. © 2011 American Institute of Physics.