We demonstrate that information on internal orientational order and size of lipoprotein particles can be extracted from the positions of their NMR spectral lines. The magnetic field obtained by solving the field equations for a model lipoprotein particle is shown to account for the hitherto unexplained size dependence of the experimental NMR frequencies. The predicted sign, magnitude, and functional form of the frequency shifts are verified by novel experimental ${}_{}{}^1{}_{}{}^{}\mathrm{H}$ NMR data from size-specifc lipoprotein samples.

• Received 24 January 1994

DOI:https://doi.org/10.1103/PhysRevLett.72.4049