To the best of my knowledge, it is not possible
readily to isolate by HPLC polar and non-polar fatty
acids. But, you can fractionate a complex pool of FAME
by a simple chromatography on a silver impregnated
column as it is explained in my site at the bottom of
the page:
http://www.cyberlipid.org/fattyt/fatt0002.htm

I used this procedure and it is very easy to run. You
will separate saturate and unsaturate fatty acids in
adapting the solvent mixture (the first one for the
saturated and the last one for the unsaturated fatty
acids).
For quantitative determination, I suggest you to
include methylated C17:0 in each fraction before GLC.

Claude Leray



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