Magnetic nanoparticles are tiny magnets of the size of large molecules. These
nanoparticles can be used as markers for biomedical analysis with remarkable
properties. By homogenous magnetic fields they can be rotated and by gradient
fields they can be steered with magnetic forces. By antibody functionalization
of their surface other proteins can be coupled to the nanoparticles. This way the
mobility of the nanoparticle is changed, which can be detected macroscopically
by the modified response to external magnetic fields. Protein interaction can
help to deliver drugs and to localize infections or inflammations for diagnostic
or therapeutic purposes by magnetic particle imaging (MPI)
