title: A robust analytical method for measurement of phytoestrogens and related metabolites in serum with liquid chromatography tandem mass spectrometry.
abstract: A sensitive and robust method using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for quantitation of 13 phytoestrogens and related metabolites in rat serum samples. A new type of column, the Kinetex core-shell C18 column, was applied for rapid separation of the target analytes in 10min. Two enzymes, sulfatase H-1 and gulcuronidase H-5 from Helix pomatia were compared on the efficiency of releasing the conjugated forms of the target analytes to their free forms in serum samples. The method detection limit (MDL) defined as three times the signal to noise ratio in spiked serum matrix-based solutions was in the range of 0.1-3.5ng/mL. The linear dynamic calibration was in the broad range of 0.2-500ng/mL for all target compounds. Thirty-two rat serum samples from the rats that were fed with diets containing either casein or soy protein isolates with various amounts of isoflavones for 8 weeks were analyzed for the target analytes with the developed method. Nine target analytes were detected in the serum samples. Those detectable compounds are all the metabolites of the dietary isoflavones, suggesting that the diet isoflavones were mostly metabolized to their metabolites in rat.
authors.affiliation: College of Science, Hunan Agricultural University, Changsha 410128, China; Exposure and Biomonitoring Division, Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Columbine Driveway, AL: 0800C, Ottawa, Ontario K1A 0K9, Canada; Nutrition Research Division, Health Products and Food Branch, Health Canada, 251 Sir Frederick Banting Driveway, Ottawa, Ontario K1A 0K9, Canada.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Exposure and Biomonitoring Division, Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Columbine Driveway, AL: 0800C, Ottawa, Ontario K1A 0K9, Canada.
authors.forename: Xiangjun
authors.initials: X
authors.lastname: Liao
authors.affiliation: Nutrition Research Division, Health Products and Food Branch, Health Canada, 251 Sir Frederick Banting Driveway, Ottawa, Ontario K1A 0K9, Canada.
authors.forename: Carla M
authors.initials: CM
authors.lastname: Wood
authors.affiliation: Nutrition Research Division, Health Products and Food Branch, Health Canada, 251 Sir Frederick Banting Driveway, Ottawa, Ontario K1A 0K9, Canada. Electronic address: chaowu.xiao@canada.ca.
authors.forename: Chao-Wu
authors.initials: CW
authors.lastname: Xiao
authors.affiliation: Exposure and Biomonitoring Division, Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Columbine Driveway, AL: 0800C, Ottawa, Ontario K1A 0K9, Canada. Electronic address: yong-lai.feng@canada.ca.
authors.forename: Yong-Lai
authors.initials: YL
authors.lastname: Feng
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005260:Female; D057230:Limit of Detection; D048789:Phytoestrogens / Q000097:blood* / Q000737:chemistry / Q000302:isolation & purification; D051381:Rats; D017207:Rats, Sprague-Dawley; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D048789:Phytoestrogens
keywords: Core–shell C18 column; High performance liquid chromatography–tandem mass spectrometry; Phytoestrogens and metabolites; Rapid separation; Rat serum