The quantitative analysis of the very-long-chain fatty acids (VLCFA) is
required for the differential diagnosis of various peroxisomal
disorders. The characteristic biochemical abnormalities in some of
these disorders are summarized in [Table 7] .
The estimation of VLCFA and phytanic acid requires preliminary
extraction and derivatization of complex lipids, followed by thin-layer
chromatographic isolation and capillary gas chromatographic analysis of
the fatty acid methyl esters.