篇名 | Analysis of Indole-3-Actic Acid in Zizania Latifolia by Single Step Ion Pair Extraction /on-Line Derivatization and Gas Chromatography-Mass Spectrometry |
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卷期 | 53:4 |
並列篇名 | 同步離子配對萃取及即時線上衍生氣相層析質譜技術應用於茭白內生吲哚乙酸之分析 |
作者 | 陳開憲 、 周繼中 、 吳香霖 |
頁次 | 419-426 |
關鍵字 | 茭白 、 即時線上衍生氣相層析質譜 、 同步離子配對 、 內生吲哚乙酸 、 Pyrolytic alkylation 、 Auxin 、 IAA-TBA ion pair 、 Injector derivatization 、 Indole-3-acetic acid-tetrabutylammonium ion pair 、 TBA-HSO 、 Tetrabutylammonium hydrogensulfate |
出刊日期 | 200712 |
本研究針對植物內生生長素吲哚乙酸之分析發展出一改良氣相層析質譜方法,並以茭白(Zizania latifolia)為方法驗證材料。本方法使用小於 1 g 的植物材料,以液態氮浴在硏缽中研碎,並加入包含緩衝液、四丁基季氨鹽離子配對/衍生劑及有機溶劑萃取溶液。此有機溶劑萃取溶液不需更進一步的純化,可直接進行氣相層析質譜分析。將 2 μL 包含吲哚乙酸四丁基季氨鹽之萃取液注入氣相層析質譜儀進樣口,在 250℃下進行即時線上衍生產生吲哚乙酸丁酯,再經 70 eV 電子轟擊式四極柱氣相層析質譜儀定性與定量。此標準注射口線上衍生吲哚乙酸丁酯的方法,提供一個簡便快速及具有可接受靈敏度的氣相層析質譜儀定性與定量分析方式。全質譜掃瞄方式的偵測極限約為每次注射吲哚乙酸5 ng,選擇離子監測(二離子)模式之偵測極限約每次注射吲哚乙酸0.5 ng。茭白筍部的游離態吲哚乙酸約在 1.55 到 6.34 μg/g F.W.,結合態吲哚乙酸約在 1,540 到 8,340 ng/g F.W.。吲哚乙酸丁酯的質量數離子(m/z = 231)在極性的DBWax 分離管柱中有較長的滯留時間,此較長之滯留時間亦有助於與植物中潛在的干擾物質分離。本方法的總回收率約為 73.9 %,相對誤差約為10.8 %。
Abstract: This work presents an improved GCMS method to analyze indole3acetic
acid, the endogenous auxin in plant samples. Zizania latifolia plant tissues were used to
evaluate this method. The method involves extraction of < 1 g samples by grinding the plant
tissue in liquid nitrogen followed by an extraction cocktail including buffer,
tetrabutylammonium ion pair/derivatizing agent and small amount organic solvent. The
extracted organic solvent was subject to GCMS analysis without further purification. The
online derivatization takes place in the injection port of GC equipped with a standard
split/splitless injection port; and 2 μL of organic extract containing the
IAAtetrabutylammonium salts was injected. The analytes were then identified and
quantitated by 70 eV electron impact quadrupole GCMS. The standard split/splitless
injectionport derivatization technique provides fast and reproducible results for IAA analysis
with moderate sensitivity. The detection limit is 5 ng IAA per injection in scan mode and 500
pg IAA per injection for 2 ions of selected ion moni toring mode. The free IAA concentration
of the edible gall of Z. latifolia ranged from 0.26 to 2.43 μg/g fresh weight, and the IAA
concentration of hydrolyzed samples ranged from 1.55 to 6.34 μg/g fresh weight. The butyl
ester of indole3acetic acid has an extended retention time on the polar DBwax GC column,
and the expanded molecular ion m/z = 231 enabled IAA butyl ester to be separated from other
potential contaminations that were present in the plant extracts. Extraction recovery of the IAA
in spiked plant samples was 73.9 % with RSD = 10.8 %.