title: Streamlined F2-isoprostane analysis in plasma and urine with high-performance liquid chromatography and gas chromatography/mass spectroscopy.
abstract: F2-Isoprostanes in plasma and urine are generally determined by labor-intensive methods requiring sample purification by solid-phase extraction and thin-layer chromatography (TLC). A streamlined and more sensitive method for the measurement of esterified plasma F2-isoprostanes was developed by replacing these steps with high-performance liquid chromatography (HPLC) using an amino column with a hexane/2-propanol gradient. Pentafluorobenzyl esters of F2-isoprostanes were prepared and purified by HPLC, silylated, and then analyzed by gas chromatography (GC) with negative chemical ionization mass spectroscopy (NCI-MS). This method permits analysis with lower plasma volumes (100 microL) and greater sensitivity (to 10 pg; allowing detection to 50 pg/mL) than provided by other methods. Urinary F2-isoprostanes can also be efficiently quantified by this method, with 8-iso-PGF2alpha being identified as a major isomer. With this procedure, esterified plasma F2-isoprostanes were found to be 8.3-fold higher in an end-stage renal failure patient on hemodialysis and urinary 8-iso-PGF2alpha was 7.1-fold higher in a cigarette smoker than respective control subjects. This method, particularly the substitution of the TLC step common to other methods with HPLC, results in a more sensitive and reproducible assay.
authors.affiliation: Antioxidants Research Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts 02111, USA. walter_lp@hnrc.tufts.edu
authors.forename: M F
authors.initials: MF
authors.lastname: Walter
authors.forename: J B
authors.initials: JB
authors.lastname: Blumberg
authors.forename: G G
authors.initials: GG
authors.lastname: Dolnikowski
authors.forename: G J
authors.initials: GJ
authors.lastname: Handelman
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D015237:Dinoprost / Q000032:analysis* / Q000097:blood / Q000652:urine; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D015237:Dinoprost