Electromagnetic separation of < 20 nm diameter magnetic nanoparticles using magnetic trap and release in an open tubular capillary

ANYL 293

Jacob S. Beveridge, jsb332@psu.edu, Department of Chemistry, The Pennsylvania State Univeristy, 104 Chemistry Research Bldg, Box #56, University Park, PA 16802
The goal of the micro total analysis system is to perform bench top chemistries in a microfluidic chip; magnetic nanoparticles (MNP) may play a crucial role in these systems. To be able to realize this, the functionalization, manipulation and separation of MNP in flowing streams must be well characterized. Our goal is to separate <20 nm diameter MNP based on their size or composition using an open tubular capillary wrapped between two narrowly spaced electromagnetic poles, between which is a strong magnetic field. It was shown that the particle retention time and trapped amount of MNP is controlled by varying the magnetic field and/or flow rate. By applying magnetic force, fluid flow and field flow fractionation theory, it is possible to determine the nanoparticles' magnetic susceptibilities. Judicious programming of the magnetic field and flow rate enables separation of different types and sizes of MNP.