From the beginnings of 1970s researchers were studying the concept of magnetic guided drug delivery method. The concept of this method is to attach the drug to the micro- or nanoparticles and then to inject them to the bloodstream. For the guidance to the targeted area, a Magnetic Resonance Imaging (MRI) device is needed. By making use of the magnetic guided drug delivery method, the quantity of the drug required to reach therapeutic levels is being reduced. Also, the drug concentration at targeted sites is increased.
Our Team has worked to develop a numerical model for magnetically guided drug delivery. The method that was developed can simulate the movement of aggregated magnetic particles in a fluid environment. The numerical model can simulate the number of resulting aggregations whose size and pattern depend on the concentration and the strength of the magnetic field.
For the propulsion model of the particles, six major forces are considered, i.e. the magnetic force from MRI’sMain Magnet static field as well as the Magnetic field gradient force from the special Propulsion Gradient Coils. The static field caters for the aggregation of nanoparticles while the magnetic gradient navigates the agglomerations.Moreover, the contact forces among the aggregated nanoparticles and the wall, and the Stokes drag force for each particle are considered, while only spherical particles are used. Finally, gravitational forces due to gravity and the force due to buoyancy are added.
The method was tested through comparison against experimental and numerical data. It was found that the present method can simulate satisfactory the experiments in a stationary fluid under a steady magnetic field. Furthermore, the model was tested for the acceleration of aggregated particles under the influence of a constant and a superimposed gradient magnetic field. The results were very close to existing experimental data in terms of velocity and aggregation size and comparable to the results from existing simulations.