Smittenberg Rienk H, Sachs Julian P
University of Washington, School of Oceanography, Box 355351, Seattle, WA 98195, USA.
J Chromatogr A. 2007 Oct 26;1169(1-2):70-6. doi: 10.1016/j.chroma.2007.09.018. Epub 2007 Sep 14.
A semi-preparative normal-phase high-performance liquid chromatography-mass spectrometry (HPLC-MS) method is presented for the purification of various alcohol fractions from total lipid extracts derived from sediments, for the purpose of hydrogen isotopic measurement by gas chromatography-isotope ratio mass spectrometry (GC-IRMS). 4-methylsterols, including the dinoflagellate-specific marker dinosterol (4,23,24-trimethylcholestan-22-en-3beta-ol), were successfully separated from notoriously co-eluting plant-derived pentacyclic triterpenoid alcohols and alkyl alcohols. We find that substantial hydrogen isotope fractionation occurs during chromatographic separation, demonstrating the importance of recovering the entire peak when subsequent hydrogen isotope analyses are to be performed. This is the first report of such hydrogen isotopic fractionation for a natural unlabelled compound.
本文介绍了一种半制备正相高效液相色谱 - 质谱联用（HPLC-MS）方法，用于从沉积物的总脂质提取物中纯化各种醇类馏分，以便通过气相色谱 - 同位素比率质谱（GC-IRMS）进行氢同位素测量。4-甲基甾醇，包括甲藻特异性标志物甲藻甾醇（4,23,24-三甲基胆甾-22-烯-3β-醇），已成功地从不明共洗脱的植物源五环三萜醇和烷基醇中分离出来。我们发现，在色谱分离过程中会发生大量的氢同位素分馏，这表明在进行后续氢同位素分析时回收整个峰的重要性。这是关于天然未标记化合物的此类氢同位素分馏的首次报道。
