Determination of peracetylated sulfoglycolipids using the azure A method

Several sulfoglycolipids, including sulfogalactosylceramide, sulfolactosylceramide, monosulfogangliotriaosylceramide, monosulfogangliotetraosylceramide, bis-sulfogangliotriaosylceramide, bis-sulfogangliotetraosylceramide, seminolipid, and lysoseminolipid, were assayed by the azure A procedure (Kean, E.L. 1968. J. Lipid Res. 9: 319-327). The color yields were different significantly among each sulfoglycolipid. The accurate determination of monosulfoglycolipids having longer carbohydrate chains than sulfolactosylceramide as well as bis-sulfoglycolipids could not be achieved because of the low color yields, turbidity, and/or formation of an additional chromogen. However, the quantitative determination of these complex sulfoglycolipids could be achieved using the azure A procedure when these compounds were assayed after peracetylation. Using the modified Kean procedure, the behavior of these sulfoglycolipids in the chloroform-methanol-water partition system was compared.