Innovative Hybrid Halbach Array for Steering Magnetic Nanoparticles Through a Bifurcation

Abstract

Magnetic nanoparticles are used in a wide range of medical applications. However, the accurate steering of the particles through the vascular system is still an open research question. Thus, this paper introduces a novel hybrid magnetic array for steering magnetic nanoparticles through a bifurcation. The array consists of permanent plus electromagnets and is based on a Halbach structure. It combines the advantages of the strong magnetic field of low-cost permanent magnets with the adjustability of electromagnets. The array is investigated numerically in a 3D model using COMSOL Multiphysics. In the simulations, the propagation of the particles in a symmetrical bifurcation is analyzed for discrete coil currents in the range of −10A to 10 A. The results reveal that for low negative currents of −1A to −0.5 A, the influence of the magnetic field of the permanent magnets can be almost completely eliminated, and only 0.5% and 0.9 %, respectively, of the particles were trapped by the magnets. Thus, the hybrid array outperforms the reference of a Halbach array fully built of permanent magnets. Overall, the proposed hybrid array is much more flexible, and the magnetic force can be adjusted more precisely compared to an array of permanent magnets.

Keywords

• halbach array
• hybrid magnetic array
• magnetic drug targeting
• magnetic nanoparticles
• steering