The sample will be affected by the magnetic field as long as it contains either protons, neutrons ... usually extract the following information from NMR spectra: Chemical shift values, coupling ...

(This is the direct through-space interaction between pairs of magnetic dipoles, not the J-coupling seen ... is unusual to achieve proton line widths less than about 0.5-1 ppm, rather unsatisfactory ...

The preferred method is based on the investigation of signals in the proton NMR spectrum associated with the lipoproteins. Variations in the size, composition, and density of lipoproteins ...