Submitted on February 22, 2007
Revised on March 30, 2007
Accepted on April 23, 2007
Quantitation of isoprostane isomers in human urine from smokers and nonsmokers by LC-MS/MS
Weiying Yan, Gary D. Byrd, and Michael W. Ogden
Human Studies Division, R. J. Reynolds Tobacco Co., Winston Salem, NC
Corresponding Author: byrdg{at}rjrt.com
A simple, rapid LC-MS/MS method was developed to identify and quantitate in human urine the isoprostanes iPF2a-III, 15-epi-iPF2a-III, iPF2a-VI, and 8,12-iso-iPF2a-VI along with the prostaglandin PGF2a and 2,3-dinor-iPF2a-III, a metabolite of iPF2a-III. Assay specificity, linearity, precision, and accuracy met the required criteria for most analytes. The urine sample storage stability and standard solution stability were also tested. The methodology was applied to analyze 24-hour urine samples collected from smokers and nonsmokers on controlled diets. The results for iPF2a-III obtained by our method were significantly correlated with results by an enzyme-linked immunosorbent assay (ELISA), although an approximate 2-fold high bias was observed for the ELISA data. For iPF2a-III and its metabolite 2,3-dinor-iPF2a-III, smokers had significantly higher concentrations than nonsmokers (513 ± 275 versus 294 ± 104 pg/mg creatinine; 3030 ± 1546 versus 2046 ± 836 pg/mg creatinine, respectively). Concentration of iPF2a-VI tended to be higher in smokers than in nonsmokers; however, the increase was not statistically significant in this sample set. Concentrations of the other three isoprostane isomers showed no trends towards difference between smokers and nonsmokers. Among smokers, the daily output of two type VI isoprostanes showed a weak correlation with the amount of tobacco smoke exposure as determined by urinary excretion of total nicotine equivalents.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
