A quantitiative LC-MS/MS method for the measurement of tocopherols, polyinsaturated fatty acids and their metabolites in human plasma and serum

A sensitive and selective LC-MS/MS method for the quantification of vitamin E (α- and γ-tocopherol), polyunsaturated fatty acids (arachidonic, eicosapentaenoic, docosahexaenoic and α-linolenic acids) and their metabolites in human plasma and serum was developed and validated. The sample treatment consisted of an enzymatic hydrolysis followed by a deproteinization and a liquid-liquid extraction. The separation was achieved by reversed phase chromatography. For each analyte, two MRM transitions were monitored in order to confirm identity. All determined compounds showed good linearity over the investigated concentration range. Method accuracy was satisfactory according to the international guidelines. Our data show that this LC-MS/MS method is suitable for the quantification of a diverse set of bioactive lipids and tocopherols in human plasma of adult and children subjects. The determined levels are in agreement with the literature, thus providing a flexible method to explore pathophysiological processes in which changes of the investigated compounds are involved.