title: Stir bar sorptive extraction with in situ derivatization and thermal desorption-gas chromatography--mass spectrometry for measurement of phenolic xenoestrogens in human urine samples.
abstract: A high-sensitivity analytical method that uses stir bar sorptive extraction (SBSE) with in situ derivatization and thermal desorption (TD)-gas chromatography-mass spectrometry (GC-MS) for the simultaneous measurement of trace amounts of phenolic xenoestrogens (PXs), such as 2,4-dichlorophenol (DCP), 4-tert-butylphenol (BP), 4-tert-octylphenol (OP), 4-nonylphenol technical isomers (NP), pentachlorophenol (PCP) and bisphenol A (BPA), in human urine samples was developed. The urine sample (1 ml) was de-conjugated by adding beta-glucuronidase and sulfatase. Then, protein precipitation was performed by the addition of acetonitrile. After centrifugation, the supernatant was diluted with purified water and subjected to SBSE with in situ derivatization and TD-GC-MS. The detection limits of DCP, BP, OP, NP, PCP and BPA in the urine samples were 20, 10, 10, 50, 20 and 20 pg ml-1 (ppt), respectively. The calibration curves for PXs were linear and had correlation coefficients higher than 0.99. The average recoveries of those analytes in the urine samples were higher than 95% (RSD: <10%, n=6) with correction using the added surrogate standards. This simple, accurate, sensitive and selective method can be used in the determination of PXs in human urine samples.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan.
authors.forename: Migaku
authors.initials: M
authors.lastname: Kawaguchi
authors.forename: Norihiro
authors.initials: N
authors.lastname: Sakui
authors.forename: Noriya
authors.initials: N
authors.lastname: Okanouchi
authors.forename: Rie
authors.initials: R
authors.lastname: Ito
authors.forename: Koichi
authors.initials: K
authors.lastname: Saito
authors.forename: Shun-ichiro
authors.initials: S
authors.lastname: Izumi
authors.forename: Tsunehisa
authors.initials: T
authors.lastname: Makino
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakazawa
mesh_terms: D000328:Adult; D004967:Estrogens / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D010636:Phenols / Q000652:urine*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015262:Xenobiotics / Q000652:urine*
chemical_list: D004967:Estrogens; D010636:Phenols; D015262:Xenobiotics