Simultaneous quantification of F2-isoprostanes and prostaglandins in human urine by liquid chromatography tandem-mass spectrometry

► Measurement of F2-isoprostanes and prostaglandins in human urine by LC–MS/MS. ► Base line separation of the isomers measured. ► Quantification of analytes over a linear dynamic range (0.05–50ng/mL). ► Excellent recoveries (79–100%), no major matrix effects and absence of carry over. ► Urinary F2-isoprostanes and PGs analysis in patients undergoing cardiac surgery. A specific and sensitive LC–MS/MS method for analysis of F2-isoprostanes (F2-IsoPs) and prostaglandins (PGs) in urine was developed and validated to examine the levels of F2-IsoPs and prostaglandin F2α (PGF2α), in human urine in patients undergoing cardiac surgery. The rapid extraction for F2-IsoPs and PGs from urine was achieved using a polymeric weak anion solid phase extraction cartridge. The base-line separation of 8-iso-PGF2α, 8-iso-15(R)-PGF2α, PGF2α, and 15(R)-PGF2α was carried out on a Hydro-RP column (250mm×2.0mm i.d., Phenomenex, CA) using a linear gradient of methanol:acetonitrile (1:1, v/v) in 0.1% formic acid at a flow rate of 0.2mL/min. The method was proved to be accurate and precise for simultaneous quantification of each analyte over a linear dynamic range of 0.05–50ng/mL with correlation coefficients greater than 0.99. The intra-day and inter-day assay precision at the lowest quality control (0.07ng/mL) level were less than 17%. The mean extraction recoveries of F2-IsoPs and PGs were in a range of 79–100%. In applications of this method to patients undergoing cardiac surgery, post-surgery urinary concentrations of 8-iso-PGF2α increased significantly in patients (n=14) who did not develop acute kidney (AKI) (pre-surgery 0.344±0.039 vs. post-surgery 0.682±0.094ng/mg creatinine, p