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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
    theaflavins;tea;SALDI;MS;TiO2NP;SPE
    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。
    利用此無機基質可減少一般傳統有機基質產生的結晶點不均勻的問題,也不會有低分子量訊號的干擾,而且此分析方法具有快速、簡單、可大量分析、操作容易等特點。
    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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