An Improved Procedure for the Enrichment of Plasma F2-Isoprostanes Prior to Final Determination by GC-MS/NICI

One of the most popular approaches to quantify oxidative injury is to measure lipid
peroxidation products and, in particular, F2-isoprostanes (F2-IPs). F2-IPs is a group of prostaglandin
F2-like compounds derived from the non-enzymatic oxidation of arachidonic acid. Of these, the
15-F2t-isoprostane (8-iso-PGF2) has received considerable attention, because it possesses adverse
biological activities. Previous Gas Chromatographic-Mass Spectrometric (GC-MS) methods for measuring
plasma F2-IPs from this laboratory involved two chromatography steps on C18 and NH2-cartridges.
Problems may, however, arise with chromatography on C18 cartridges, as it can be time-consuming
and losses may occur depending upon the pH and eciency of the sample loading. Therefore, it was
decided that the C18 chromatography step be replaced with a single lipid partitioning step and the
NH2-chromatography be simplied. In 70 plasma samples from healthy individuals, total (sum of free and
esteried) 15-F2t-isoprostane concentrations ranged from 0.5 to 3.13 nM. This assay meets all predened
method performances in terms of specicity and sensitivity. The improved method is suitable for the
analysis of samples from larger clinical trials investigating the role of oxidant injury under conditions
associated with oxidative stress.
One of the most popular approaches to quantify oxidative injury is to measure lipid
peroxidation products and, in particular, F2-isoprostanes (F2-IPs). F2-IPs is a group of prostaglandin
F2-like compounds derived from the non-enzymatic oxidation of arachidonic acid. Of these, the
15-F2t-isoprostane (8-iso-PGF2) has received considerable attention, because it possesses adverse
biological activities. Previous Gas Chromatographic-Mass Spectrometric (GC-MS) methods for measuring
plasma F2-IPs from this laboratory involved two chromatography steps on C18 and NH2-cartridges.
Problems may, however, arise with chromatography on C18 cartridges, as it can be time-consuming
and losses may occur depending upon the pH and eciency of the sample loading. Therefore, it was
decided that the C18 chromatography step be replaced with a single lipid partitioning step and the
NH2-chromatography be simplied. In 70 plasma samples from healthy individuals, total (sum of free and
esteried) 15-F2t-isoprostane concentrations ranged from 0.5 to 3.13 nM. This assay meets all predened
method performances in terms of specicity and sensitivity. The improved method is suitable for the
analysis of samples from larger clinical trials investigating the role of oxidant injury under conditions
associated with oxidative stress.