Quantification of F_(2)-isoprostanes in urine by liquid chromatography tandem mass spectrometry (LC-MS/MS)

摘要

F_(2)-isoprostanes (F_(2)-IsoPs), are a family of prostaglandin-like compounds produced in vivo via a non-enzymatic mechanism involving the free radical-initiated peroxidation of arachidonic acid, and have been the subject of intense study owing to their role as a biomarker for oxidative stress and cell membrane damage. Identification of such compounds at physiological concentrations in biological systems has immense implication for many areas of research. It is, therefore, necessary to have analytical methods which are sensitive, reproducible, and simple. A LC-MS/MS method operating in the MRM mode was developed that allows for the characterization and simultaneous quantification of isomeric isoprostanes including: 8-iso-PGF_(2alpha), 8-iso-15(R)-PGF_(2alpha), and 8-iso-PGF_(2alpha)-D4(internal standard) and prostaglandins PGF_(2alpha), 15(R)-PGF_(2alpha) over a linear dynamic range of 0.05-50 ng/mL with accuracies 88-121percent. The separation was carried out on a Hydro-RP column (250 X 2.0 mm i.d) column consists of water and methanol: acetonitrile (1:1 v/v) (both containing 0.1percent formic acid) with a flow rate of 0.2 mL/min. This method is very useful for the analysis of individual F_(2)-IsoPs and PGs and proved to be simple, sensitive, reproducible, faster than previous published methods, and sufficiently reliable to assess oxidative status and inflammatory conditions in both clinical and research studies.