English  |  正體中文  |  简体中文  |  Items with full text/Total items : 70588/70588 (100%)
Visitors : 23151960      Online Users : 642
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version

    Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/5997

    Title: 以氣相及液相層析質譜儀分析具荷爾蒙效應物質之方法開發;Determination of endocrine disrupting chemicals in different matrices using GC/MS and LC/MS.
    Authors: 郭瀚文;Han-Wen Kuo
    Contributors: 化學研究所
    Keywords: 雌性激素;外因性內分泌干擾物質;環境荷爾蒙;異黃酮素;液相層析質譜儀;氣相層析質譜儀;類固醇荷爾蒙;植物性雌激素;雙酚-A;bisphenol A;steroid hormones;isoflavones;estrogens;phytoestrogen;gas chromatography-mass spectrometry;environmental hormones;Endocrine disrupters;liquid chromatography-mass spectrometry
    Date: 2004-06-25
    Issue Date: 2009-09-22 10:11:38 (UTC+8)
    Publisher: 國立中央大學圖書館
    Abstract: 17β-Estradiol (E2)、estrone (E1)、estriol (E3)等天然的雌性激素化合物及其代謝物與17α-ethinylestradiol (EE2)、diethylstilbestrol (DES)等人工合成的雌性激素化合物,其荷爾蒙效應均高於多氯聯苯、塑化劑、烷基酚類等內分泌干擾物質,對於生物體在發育、生長、行為、繁殖等方面影響甚鉅。所以近幾年來,許多研究即是針對上述物質在水環境中分布的情形進行分析檢測。 本研究目標之一為建立一套以固相萃取法搭配液相層析質譜儀檢測日常用水中E1、E2、E3、EE2、DES等五種天然與人工合成的雌性激素類化合物之分析方法。首先針對液相層析質譜儀之游離介面與使用的動相組成,進行游離效果之比較,結果顯示以氰甲烷/ 0.1%氨水水溶液為組成動相之溶劑,在電灑游離法負離子模式分析下,可以得到最佳的感度。接著以上述的游離與層析條件,搭配Oasis® HLB固相萃取管柱,針對含有10 ng/L分析物之1 L水樣進行回收率的探討,在最佳條件下各分析物之回收率均高於77%,相對標準偏差在7%以下,顯示本方法具有良好的回收率與再現性。針對中壢地區地下水以及自來水的研究結果,均未檢測出雌性激素類污染物之存在,顯示本地的水源並未受到污染。 另外本研究也針對嬰兒配方奶粉中的內分泌干擾物質daidzein (De)、genistein (Ge)與bisphanol A (BPA),進行分析方法之開發。這三種化合物的荷爾蒙效應雖然僅為E2的10-4倍,然而對於長期食用嬰兒奶粉的兒童,在生殖系統與發育過程仍有一定的風險存在。 分析方法是利用超音波震盪、高速離心以及過濾,將分析物由奶粉萃取至溶劑當中,搭配C18 SPE管柱進行濃縮與淨化工作,再以矽烷化衍生試劑BSTFA將三種化合物衍生化後注射至氣相層析質譜儀分離與檢測。實驗結果顯示三種化合物的萃取回收率均在79%以上,相對標準偏差值也低於10%。而在市售嬰兒配方奶粉的檢測結果,發現所有奶粉均含有BPA (45-113 ng/g)、De (20-2050 ng/g)與Ge (21-6510 ng/g),其中大豆配方奶粉含有高濃度的植物性雌激素De與Ge (2050 ng/g與6510 ng/g)。 Society has been very concerned with the potential risk to human life and wildlife due to exposure to both natural and synthetic estrogenic chemical residues that may interfere with reproduction and development. Although the concentration of these compounds in environmental samples is low, it has been demonstrated that the nonconjugated estrogens at low concentrations can cause the synthesis and secretion of vitellogenin in male fish. This study describes a reliable and sensitive method for determining five estrogenic compounds by liquid chromatography/mass spectrometry (LC/MS). Optimization of the ionization process was performed with electrospray ionization, atmospheric pressure chemical ionization and atmospheric pressure photoionization methods using three eluents with different compositions in the LC/MS scan mode, and using both positive ion and negative ion modes. The best ionization sensitivity for the studied compounds was obtained with ESI in negative ion mode when using an acetonitrile-water gradient including 0.1% of ammonium hydroxide (pH 10.7). Using the optimum conditions equipped with reliable pretreatment procedures, the quantitation limit of these compounds was 10 ng/L in 1 L water samples. Recovery of the estrogenic chemicals in spiked various water samples ranged from 77 to 99% while RSD ranged from 1 to 6%. Another investigation describes a reliable and sensitive method for simultaneously determining bisphenol A (BPA) and two major phytoestrogens, daidzein and genistein, in powdered milks and infant formulas by gas chromatography–mass spectrometric analysis after trimethylsilylation. To reduce the matrix interference associated with the constituents of the formulas, the dissolved formula solutions were firstly ultra-centrifuged and the analytes in the supernatant were then extracted using a C18 solid-phase extraction cartridge. The accuracy and precision of the method were determined and the technique was successfully employed to measure trace concentrations of bisphenol A, daidzein and genistein in powdered formulas. The results show that bisphenol A, daidzein and genistein were detected in all the testing samples at concentrations from 45 to 113 ng/g (except one infant formula), 20 to 2050 ng/g and 21 to 6510 ng/g, respectively. The highest concentrations of daidzein and genistein (i.e., 2050 and 6510 ng/g) were detected in a soy-based powdered infant formula. The quantitation limits were 1.0 ng/g for bisphenol A, and 10 ng/g for daidzein and genistein using 0.5 g powdered milk samples.
    Appears in Collections:[化學研究所] 博碩士論文

    Files in This Item:

    File SizeFormat

    All items in NCUIR are protected by copyright, with all rights reserved.

    社群 sharing

    ::: Copyright National Central University. | 國立中央大學圖書館版權所有 | 收藏本站 | 設為首頁 | 最佳瀏覽畫面: 1024*768 | 建站日期:8-24-2009 :::
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback  - 隱私權政策聲明