Development of a Two-Way Coupled Eulerian-Lagrangian Computational Magnetic Nanoparticle Targeting Model for Pulsatile Flow in a Patient-Specific Diseased Left Carotid Bifurcation Artery.

Purpose: The aim of the present work is to present the development of a computational two-way coupled (fluid and particle coupled) magnetic nanoparticle targeting model to investigate the efficacy of magnetic drug targeting (MDT) in a patient-specific diseased left carotid bifurcation artery. MDT of therapeutic agents using multifunctional carrier particles has the potential to provide effective treatment of both cancer and cardiovascular disease by enabling a variety of localized treatment and diagnostic modalities while minimizing side effects.

Methods: A computational model is developed to analyze pulsatile blood flow, particle motion, and particle capture efficiency in a diseased left carotid bifurcation artery using the magnetic properties of magnetite (FeO) and equations describing the magnetic forces acting on particles produced by an external cylindrical electromagnetic coil. A Eulerian-Lagrangian technique is adopted to resolve the hemodynamic flow and the motion of particles under the influence of a magnetic field (B= 2T). Particle diameter sizes of 20 nm-4 μm in diameter were considered.

Results: The computational simulations demonstrate that the greatest particle capture efficiency results for particle diameters within the micron range, specifically 4 µm in regions where flow separation and vortices are at a minimum. It was also determined that the capture efficiency of particles decreases substantially with particle diameter, especially in the superparamagnetic regime. Particles larger than 2 μm were targeted and captured at the desired location by the external magnetic field, and the largest capture efficiency observed was approximately 98%.

Conclusion: The simulation results presented in the present work have shown to yield favorable capture efficiencies for micron range particles and a potential for enhancing capture efficiency of superparamagnetic particles in smaller arteries and/or using magnetized implants such as cardiovascular stents. The present work presents results for justifying further investigation of MDT as a treatment technique for cardiovascular disease.