title: On-chip diamagnetic repulsion in continuous flow.
abstract: We explore the potential of a microfluidic continuous flow particle separation system based on the repulsion of diamagnetic materials from a high magnetic field. Diamagnetic polystyrene particles in paramagnetic manganese (II) chloride solution were pumped into a microfluidic chamber and their deflection behaviour in a high magnetic field applied by a superconducting magnet was investigated. Two particle sizes (5 and 10 μm) were examined in two concentrations of MnCl2(6 and 10%). The larger particles were repelled to a greater extent than the smaller ones, and the effect was greatly enhanced when the particles were suspended in a higher concentration of MnCl2. These findings indicate that the system could be viable for the separation of materials of differing size and/or diamagnetic susceptibility, and as such could be suitable for the separation and sorting of small biological species for subsequent studies.
authors.affiliation: Department of Chemistry, The University of Hull, Cottingham Road, Hull HU6 7RX, UK.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Tarn
authors.affiliation: Nano Ceramics Center, National Institute for Materials Science, Tsukuba 305-0047, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Hirota
authors.affiliation: Department of Chemistry, The University of Hull, Cottingham Road, Hull HU6 7RX, UK.
authors.forename: Alexander
authors.initials: A
authors.lastname: Iles
authors.affiliation: Department of Chemistry, The University of Hull, Cottingham Road, Hull HU6 7RX, UK.
authors.forename: Nicole
authors.initials: N
authors.lastname: Pamme
keywords: continuous flow; diamagnetic repulsion; microfluidic; microparticles; superconducting magnet