CHARACTERIZATION OF SOYBEAN PHOSPHATIDYLCHOLINE PURITY BY H-1 AND P-31 NMR

A strategy is proposed to evaluate the purity of phosphatidylcholine from soybean lecithin, obtained by extraction or column chromatography, using the integrals ratio of H-1 NMR spectra. Integrals of methylene signals, around 1.3 and 1.6 ppm, are added and divided by the integral of the choline methyl groups, around 3.3 ppm. Before purification, a ratio of 19.68 +/- 1.37 was determined. Using extraction, a ratio of 10.70 +/- 0.61 was found, while from column chromatography, a value of 2.99 +/- 0.25 was detected. P-31 NMR of standard phosphatidylcholine showed signals at -0.2 and -0.9 ppm, whereas the purified one showed a single signal at -0.9 ppm.