Fast HPLC determination of serum free fatty acids in the picomole range

We developed a method for determining individual free fatty acids in serum by using a modified one-step Dole extraction, derivatization, and a new high-performance liquid chromatographic (HPLC) separation. Sample han-dling is minimized to a single transfer of the fatty acids (upper layer of the Dole extract), which are readily deriva-tized at 85 #{176}Cwith p-bromophenacyl bromide without significant hydrolysis of esterifled fatty acids. The deriva-tization mixture is directly injected into the HPLC appara-tus. The new method, which uses C6 (3-zm particle) column material and an isocratic acetonitrile-water eluent, separates nearly to baseline 12 of the physiolog-ically most abundant long-chain fatty acids (C12-C) in <20 mm with a detection limit of-2 pmol. It is therefore suitable for routine analysis even with basic HPLC equip