Abstract
We report on the facile and switchable alignment of superparamagnetic iron oxide nanoparticles measuring similar to 18 nm in diameter in electrospun microfibers. Application of a magnetic field perpendicular to the electric field employed during electro-spinning yields polymeric microfibers with nanoparticles aligned in one-dimensional arrays, thereby providing control over when and where the nanoparticles align. According to electron microscopy, the length over which alignment is desired can be judiciously selected, thereby making these nanomaterials excellent candidates for nanotechnologies requiring nanoscale alignment on-demand. Concurrent alignment of the electrospun fibers using established procedures provides a viable route to organic/inorganic materials possessing anisotropic properties that reflect multiscale alignment.