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    高師機構典藏 NKNUIR > 理學院 > 化學系 > 博碩士論文 >  Item 987654321/15761
    Please use this identifier to cite or link to this item: http://ir.nknu.edu.tw/ir/handle/987654321/15761

    題名: 以固相萃取技術結合表面輔助雷射脫附游離-飛行時間質譜法分析茶葉中茶黃素的含量
    Determination of theaflavins in tea by solid-phase extraction coupled with surface-assisted laser desorption/ionization mass spectrometry
    Authors: 陳淨容
    Ching-Jung Chen
    貢獻者: 楊慶成;張玉珍
    Ching-Cherng Yang;Yu-Jan Chang
    Keywords: 茶黃素;茶葉;表面輔助雷射脫附游離質譜法;二氧化鈦奈米粒子;固相萃取
    Date: 2011-08-16
    Issue Date: 2011-09-19 16:57:31 (UTC+8)
    Abstract: 茶黃素是一種存在於紅茶中的金黃色色素,為多酚類化合物,而茶黃素類化合物是由茶葉在發酵過程中,兒茶素類化合物氧化聚合而成的產物,越來越多研究指出茶黃素類化合物具有各種優異的生物活性,茶葉中茶黃素類化合物含量的多寡也是茶葉品質的衡量標準,於是檢測茶葉中的茶黃素含量是本研究的主要目的。
    本研究中利用固相萃取技術(SPE)純化並濃縮茶葉中的茶黃素類化合物,使用二氧化鈦奈米粒子(TiO2NPs)當作基質,以表面輔助雷射脫附游離飛行時間質譜法(SALDI-TOF MS)進行分析偵測。
    這套茶黃素類化合物的分析方法成功應用於茶葉樣品的分析,其theaflavin(TF)、theaflavin monogallate(TFMG)、theaflavin 3,3’-digallate(TFDG)偵測極限(S/N=3)分別為7.5 μg/mL、10 μg/mL、5 μg/mL。在真實樣品方面使用標準添加法進行定量,回收率則介於77.5% - 82.0%之間。
    The aim of the this study was to develop a rapid method for extracting four TFs from teas samples with a solid-phase extraction(SPE) technique and subsequently measure their concentrations using a surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) system.
    The three TFs in black tea leaves were extracted with 70% aqueous ethanol. The ethanol extracts were diluted 4-fold with deionized water. All diluted extracts were directly applied to the solid-phase C18 cartridge column, and then the TFs was eluted by 95% ethanol and apply to analysis. Various parameters that would influence the ionization efficiency and sensitivity of matrix in the MALDI-MS were examined, this study choose 50 μg/mL Titanium(IV) oxide 32nm as matrix and use negative mode to analysis TFs.
    By using the optimal conditions, the detection is linear in the range of 10 - 500 μg/mL for TF and TFDG, and 20 – 400 μg/mL for TFMG, the correlation coefficients (r2) above 0.9921, the detection limits (LOD) of 7.5 μg/mL、10 μg/mL and 5 μg/mL for TF、TFMG and TFDG, respectively. By the SALDI-MS couple with SPE, it can be successful to detect the TFs in the tea sample.
    Appears in Collections:[化學系] 博碩士論文
    [化學系] 張玉珍
    [化學系] 楊慶成

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