Current magnetic resonance imaging (MRI) can only provide monochromatic contrast. Introducing spectroscopic multiplexed “color” to MRI can be extremely useful for applications including cell tracking and soft tissue pathology. This research will initiate a collaborative effort to develop nanosize magnetic tags as a new type of contrast agent to improve MRI sensitivity, signal to noise ratio and more importantly introduce spectroscopic resolution. Different from conventional Gadolinium compound and super-paramagnetic nanoparticle contrast agents (CAs) where the monochromic contrast is enhanced due to the proton relaxation time (T1, T2, or T2 *) alternation caused by the continuously varying magnetic field, distinguishable nuclear magnetic resonance (NMR) spectra can be recorded by engineering the localized magnetic fields generated by magnetic nanotags through size, shape and structure control. This seed program will support the study of material selection, magnetic field design, nanofabrication, water molecule diffusion control, selective nanotag surface functionalization and biocompatibility, nanotag dispersion in fluids; and in vitro MRI spectroscopic and sensitivity characterization. This project will combine the PIs’ expertise in clinical MRI research, nanostructure synthesis, nanofluids, and bio-materials to build the foundation towards the development of in vivo “colorful” MRI imaging. The nano-materials enabled MRI imaging technique can greatly improve MRI diagnostic capability and when incorporated with nanoscale targeted drug delivery and localized treatment, the research development will help the military to diagnose and treat personnel in the field of oncology and beyond.