A Simple and Highly Sensitive Quantitation of Eicosanoids in Biological Samples Using Nano-flow Liquid Chromatography/Mass Spectrometry.

A simple sample preparation method for eicosanoid was developed by the combination of deproteinization and nanoLC-ESI-MS/MS. Eicosanoids are a group of bioactive lipid mediators, present in trace amounts in the body. Therefore, an analytical method for eicosanoids requires superior sensitivity. The method described in this report, which takes advantage of the highly sensitive power of nanoLC-ESI-MS/MS, enabled a simplification of the sample-preparation process. Eicosanoid extraction was performed just by homogenization in methanol with subsequent phospholipid removal, and then the liquid phase was directly subjected to nanoLC-ESI-MS/MS analysis without a condensation process. The quantitation range achieved 0.01 - 100 ng/mL for thromboxane B2 , and 0.05 - 100 ng/mL for prostaglandin E2 , prostaglandin D2 , prostaglandin F2 , leukotriene B4 , 6-keto prostaglandin F1α and 11-dehydro thromboxane B2 . Rat brain sample analyses demonstrated the feasibility of the quantification of those seven eicosanoids from biological samples.