Figure 1: Survey of lipid analysis by MALDI MS. The sample of interest is first extracted with organic solvents, spiked with one or more standards and subsequently mixed with the matrix. A combination of acidic (such as 2,5-dihydroxybenzoic acid (DHB)) and alkaline (such as 9-aminoacridine (9-AA)) matrices should be used to record positive and negative ion spectra, respectively. The combined analysis of the positive and negative ion spectra provides a maximum of information. Lipid mixtures maybe also separated by TLC and subsequently the individual spots analyzed by MS. Abbreviations: LPC, lyso-phosphatidylcholine; PC, phosphatidylcholine; PE, phosphatidylethanolamine; PI, phosphatidylinositol; SM, sphingomyelin; TAG, triacylglycerol.