The present inventions relate to compositions and methods for imaging and treating atherosclerotic diseases, pathogen infections, and tumors by administering actively targeting magnetic nanoparticles. In particular, the present inventions provide new types of targeting ligands attached to magnetic nanoparticles for magnetic resonance imaging. The use of these targeted magnetic nanoparticles is contemplated as a means to treat atherosclerotic diseases, including but not limited to inhibiting and removing atherosclerotic plaques. Further, actively targeting magnetic nanoparticles are contemplated for use with multiple labels for use in nuclear medicine imaging, computed tomography (CT) techniques and other types of imaging for medical and research applications.
