Permanent magnets to enable highly-targeted drug delivery applications: A computational and experimental study

Abstract

Nanoparticle-based therapies have gained considerable attention over the past few years as potential candidates for the development of robust treatments for degenerative conditions such as Parkinson’s or Alzheimer’s. A major challenge to increase the specificity of such therapies is the limited control over their fate and transport upon administration. An avenue to overcome this issue is to immobilize the therapeutic molecules on magnetically responsive nanostructures. This allows a direct control via magnetic fields generated through either permanent or electromagnets. Permanent magnets offer technical and economic advantages over electromagnets but their spatial disposition needs to be dynamically adjusted to assure proper magnetic gradient directionality. The engineering of such a dynamic system requires a detailed understanding of the impact of changing the number and relative positions of magnets in close proximity to the particles, which can be tedious to achieve experimentally. Alternatively, electromagnetic modeling and simulation provides a rather expedite route to explore multiple configurations. Here we evaluate, against experimental data, the robustness of electromagnetic models incorporated in the software COMSOL® to predict field gradients and intensities. We tested two of the incorporated meshing approaches in a single magnet and an array of two magnets. Our findings indicate that the two approaches fitted the experimental data as evidenced by the statistical significance of various correlation indexes.