Modification of Néel and Brownian relaxation properties of nanoparticles for magnetic imaging methods

The project is focused on the preparation of magnetic nanoparticles with nearly monodisperse cores that are superparamganetic at the working temperatures and biologically inert coatings optimized for magnetic particle imaging (MPI) and supplemental use as contrast agents in MRI. As regards the MPI signal, the Néel and Brownian relaxation of intended particles will be optimized by means of their intrinsic magnetic properties (magnetization and magnetocrystalline anisotropy), the size and shape of their magnetic cores and the thickness and frictional properties of their coating. Specifically, zinc-doped magnetite is considered as the suitable core material, whereas mostly inorganic shells based on silica, titania and gold or monomolecular coatings, enabling different Brownian relaxation, will be employed. The rigorous development will significantly enhance the signal in MPI, which will be studied by a unique imaging system. The detailed physical studies devoted primarily to structure and magnetism will allow for detailed understanding and development of improved imaging agents.