Analysis of F2 -isoprostanes in plasma of pregnant women by HPLC-MS/MS using a column packed with core-shell particles

Abstract

Plasma F2 -isoprostanes (F2 -isoPs) are reliable biomarkers of oxidative stress. Several possible F2 -isoPs are generated by the oxidation of arachidonic acid esterifi ed in phospholipids. The separation of these isomers represents a technical challenge for rapid and selective determination. We have developed a HPLC-MS/MS method for the simultaneous determination of seven plasma F2 -isoPs, namely 8-iso- 15(R)-prostaglandin F 2α (PGF 2α ), 8-iso-PGF 2α , 15(R)-PGF 2α , iPF 2α -IV, iPF 2α -VI, 5-iPF 2α -VI, and (±)5-8,12-iso-iPF 2α -VI. We have validated this method in plasma of pregnant women, a mild physiological oxidative stress known to increase F2 -isoPs. Thus, plasma samples of women collected at the third trimester of pregnancy (n = 20) were subjected to alkaline hydrolysis followed by liquid-liquid extraction in order to extract total F2 -isoPs. The F2 -isoPs were separated within 16.5 min using a column packed with core-shell particles. The class VI isomers were the most abundant, accounting for 65% of the total level of all quantifi ed F2 -isoPs in plasma of pregnant women ( P < 0.05). The 15(R)-PGF 2α was the most abundant of the class III isomers quantifi ed. This method allowed fast and selective separation of seven isomers from three different classes of F2 -isoP regioisomers . Copyright © 2013 by the American Society for Biochemistry and Molecular Biology, Inc.