Separations of lipids by silver ion chromatography.

The possibility of separating lipid materials on the basis of the number, type, and position of the unsaturated centers they contain, by virtue of the complexing of these unsaturated bonds with silver ions, provides a relatively recent but now very important addition to the range of separatory methods available to lipid chemists and biochemists. In this review, the nature of the complexing of silver ions with olefins is considered briefly and the history of the development of separation methods based on argentation is traced. Some practical considerations of argentation chromatography are discussed and separations of fatty acids and aldehydes, substituted fatty acids, neutral lipids, polar lipids, and sterols and other terpenoid compounds, by argentation methods alone and in conjunction with other separation techniques, are then reviewed. Some conclusions are finally presented as to the present and potential utility of argentation methods in studies of the occurrence, metabolism, and function of lipids.