Magnetic Field Effect on the Magnetic Nanoparticles Trajectories in Pulsating Blood Flow: a Computational Model

Magnetic drug targeting is a non-invasive biomedical technique for the treatment of localized diseases. This technique is based on the bonding of the drug to the nanoparticles’ surface with a magnetizable core, suspended in a liquid known as ferrofluid that is injected into the bloodstream and directed to the target region through external magnetic fields. In this article, the kinetic behavior of a magnetic nanoparticle subjected to external magnetic fields at four moments of the cardiac cycle is compared to understand the dynamic effect due to the blood pulsating. For it, a 100 μm diameter non-bifurcated and radially symmetrical blood vessel is approximated with pulsating flux and a 100 nm radius magnetic nanoparticle, driven by external magnetic fields associated with a cylindrical neodymium magnet. Two forces are taken into account: the magnetic force on the nanoparticle and the drag force influenced by the velocity profiles of the blood flow as well as its velocity. The effects of gravity and thermal are not taken into account. In the results, a proportional relationship was obtained between the shape of the velocity profile caused by the moment of the cardiac cycle with the trajectories of the nanoparticles, where capture in the early and late cardiac relaxation phase is facilitated.