Magnetic trap effects on nanowire’s dynamics within micro-capillary vessels

Abstract

The concept of using magnetic nanowires (NWs) as carriers in magnetic drug targeting was largely developed in the last decade. Magnetically controlled and manipulated nanoparticles are gaining more and more ground in various biomedical applications: drug delivery, cancer therapy by magnetic fluid hyperthermia, radiotherapy. In this study, a 2-D mathematical model was developed and implemented to examine the capture of magnetic drug carrier particles within a magnetic trap represented by high magnetic field gradients. The transient dynamics of magnetic NWs under the effect of the blood velocity (vB) varied from 0.05 up to 1.0 cm/s, magnetic field strength and their initial position within the fluid channel have been analyzed using COMSOL Multiphysics module. The parameters related to the NW with strong influence on the magnetic trap output were systematically modified: magnetic material, cylindrical particle geometry characterized by diameter and length, its initial position related to both fluid flow direction and distance from the channel center. Considering the influence of both hydrodynamic, magnetic forces and torques the magnetic trap’s efficiency was evaluated and phase diagrams were determined for different parameters involved. A considerable number of simulations were made to obtain statistically significant results. These results are commented and discussed in detail.