LC-MS/MS assay for the simultaneous determination of tocopherols, polyunsaturated fatty acids and their metabolites in human plasma and serum

• Published in: Free radical biology & medicine 2019-11, Vol.144, p.134-143
• Main Authors: Giusepponi, Danilo, Galarini, Roberta, Barola, Carolina, Torquato, Pierangelo, Bartolini, Desirée, Moretti, Simone, Saluti, Giorgio, Gioiello, Antimo, Libetta, Carmelo, Galli, Francesco
• Format: Article
• Language: English
• Subjects: Eicosanoids; Human plasma/serum; Liquid-chromatography tandem-mass spectrometry (LC-MS/MS); Polyunsaturated fatty acids; Tocopheryl quinone; Validation; Vitamin E
• ISSN: 0891-5849; 1873-4596
• DOI: 10.1016/j.freeradbiomed.2019.04.017

The role of vitamin E in both enzymatic and free radical-dependent metabolism of polyunsaturated fatty acids (PUFAs) has been well demonstrated. This study proposed a new LC-MS/MS method to quantify the main vitamin E forms, their metabolites and main PUFA species in human blood, since, at present, there are not procedures able to simultaneously determine these two classes of compounds. After the optimization of sample treatment and reverse-phase separation conditions, tandem mass spectrometry detection was evaluated experimenting both positive and negative electrospray ionisation modes. The procedure was also preliminarily adapted to assess five arachidonic acid-derived eicosanoids that could be under the influence of vitamin E function, such as LTB4 (leukotriene B4), 20-HETE (20-hydroxyeicosatetraenoic acid) and their ω-oxidation metabolites. After the validation study, the performance characteristics were confirmed analysing a certified reference material (SRM® 1950 - frozen human plasma by NIST). Finally, an application of the method in the analysis of lipid abnormalities of chronic kidney disease patients was shown. [Display omitted] •Simultaneous determination of vitamins E, PUFAs and metabolites in blood.•Satisfactory validation data were obtained.•Quality assurance issues have been stressed analyzing a CRM (plasma).•A stability study was carried out at −20 °C and −80 °C for four months.•Preliminary data evidenced differences between healthy subjects and renal patients.