Immunomagnetic nanoparticles are used as a contrast agent for enhancing medical diagnostic imaging such as magnetic resonance imaging (MRI). The present invention is directed to methods of making targeted MRI contrast agents from immunomagnetic particles and to methods of using such MRI contrast agents. Typically, such targeted MRI contrast agents provide enhanced relaxivity, improved signal-to-noise, targeting ability and resistance to agglomeration. Methods of making such MRI contrast agents typically afford better control over particle size and methods of using such MRI contrast agents typically can afford enhanced blood clearance rates and distribution. The ability to use the contrast agents im MRI provides a tool in the diagnosis and treatment of several disease states.
