Fig. 4
The magnetic field generator and their magnetic field uniformity and PEI-SPIO-NPs distributed in the different magnetic field. a Measurement of magnetic field uniformity by Graussmeter. b Uniform magnetic field generator. c 3D image of magnet arrangement of uniform magnetic field generator (where each magnet has a size of 40 × 40 × 200 mm3). d 96-well magnetic field generator. e Magnetic field uniformity of 96-well magnetic field generator. f Magnetic field uniformity of uniform magnetic field generator. g Distribution of PEI-SPIO-NPs in 96-well magnetic field. h Distribution of PEI-SPIO-NPs in uniform magnetic field. i The XOY plane distribution of uniform magnetic field (50 mm × 50 mm) and j 3D distribution of uniform magnetic field