Chapter 1 General Strategies for Practical Chromatographic Analysis of LIPIDS

Abstract

This chapter discusses the general strategies for practical chromatographic analysis of lipids. The great complexity of natural lipid mixtures necessitates a combined application of two or more complementary methods of chromatography for effective separation. As a minimum, an initial separation into lipid classes must precede the subsequent resolution into molecular species. Such lipid classes as triacyl glycerols require a preliminary segregation into subclasses before a final resolution into molecular species can be accomplished. In many instances both initial segregation into classes and the subsequent resolution into species can be accomplished without the introduction of protective groups. The preparation of special UV absorbing or fluorescent derivatives usually facilitates the detection and quantitation of both major and minor components during HPLC. The preparation of the TMS, t-BDMS and the pentafluorobenzoates greatly facilitates the detection and quantitation of many lipid species during GC/MS and LC/MS. In specific instances the preparation of appropriate derivatives has decreased the minimum detection limit from low nanogram to high pictogram range. These levels of sensitivity are comparable to those obtained for the detection of glycolipids by means of antiglycolipid antibodies. The scale down of the analysis to the subnanogram level requires specialized analytical equipment and monitoring routines.