Lipids can usually be extracted easily from tissues by making use of their hydrophobic characteristics. However, such extractions yield a complex mixture of different lipid classes which have to be purified further for quantitative analysis. Moreover, the crude lipid extract will be contami nated by other hydrophobic molecules, e.g. by intrinsic membrane proteins. Of the various types of separation processes, thin layer and column chromatography are most useful for intact lipids. High performance liquid chromatography (HPLC) is also rapidly becoming more popular, especially for the...