Computational study of superparamagnetic nanocapsules crossing the blood-brain barrier: A robotics approach

This work proposes molecular dynamics simulations used to derive guidelines for the design of the superparamagnetic nanocapsules (spherical-like or tubular-like) dedicated to cross the brain-blood barrier by magnetic forces. We focus our study on capillaries that have opened fenestrations when the integrity of the endothelial barrier is perturbed by tumors. We identified three different categories of governing parameters: geometrical (radius and length of nanocapsules); biophysical (ligand-to-receptor surface density ratio; non-specific interaction parameter) and biological (ligandreceptor binding affinity). It was demonstrated from MD simulations that the optimized size was for CNTs with dimensions greater than for 20 to 200 nm. Finally, the simulation results show that the superparamagnetic nanorobotic capsules were able to cross the endothelial barrier by using magnetic forces compatible with medical constraints.