Targeted medication delivery using magnetic nanostructures

We use quaternion molecular dynamics simulations to describe field-induced structural transitions in systems of few magnetic dipoles and their use for targeted medication delivery. Compact ring isomers of magnetic particles are contained, together with molecules of an active medication, inside inert microcapsules. The filled microcapsules may be transported within the body using a weak, inhomogeneous magnetic field. Medication release is triggered by puncturing the container during a structural transition within the magnetic subsystem, induced by an externally applied strong magnetic field. Our simulations describe not only the time evolution of the magnetic subsystem during a successful medication release, but also address ways to suppress an accidental release induced by thermal and magnetic fluctuations. (Some figures in this article are in colour only in the electronic version)