US Patent 7960025 - Magnetic nanoparticle with noble metal core

http://www.freepatentsonline.com/7960025.html

This patent teaches applications of magnetic nanoparticles in biomedicine, as tools for biomolecule recognition, in nuclear magnetic resonance imaging, drug-release control, and hyperthermia treatments. Claim 1 reads:

1. Magnetic nanoparticles of noble metals having a size of less than 5 nm, the nanoparticles comprising:

a) a core formed from a noble metal and

b) an anisotropic layer formed from compounds containing at least one metal-sulphur covalent bond wherein the nanoparticles display ferromagnetic behavior at room temperature and a hysteresis cycle, and further wherein the nanoparticles are formed from a non-ferromagnetic precursor noble metal.