Molecular order sensitive MRI

We discuss a contrast method for nuclear magnetic resonance imaging (MRI) based on the nutation frequency dispersion of the NMR signal amplitude in the rotating frame. As a practical matter, we test the concept using a specially designed phantom with independent compartments containing doped water (with copper sulfate) and a liposome suspension prepared with dimyristoylphosphatidylcholine. This last was chosen due to the strong nutation frequency dispersion the sample shows as a consequence of the particular molecular order and dynamics of the lipids within the unilamellar membrane, a key factor for the proposed experiment. The used sequence for 1D imaging is a combination of a previously reported fixed lock-time relaxation experiment in the rotating frame and a simple gradient spin-eco. Gross differences exist between T_1ρ-weighted images in the rotating frame and the approach here presented.