Enhancement of detection for partially methylated alditol acetates by chemical ionization mass spectrometry.
Enhancement of detection for partially methylated alditol acetates by chemical ionization mass spectrometry.
复制标题
通过化学电离质谱法增强部分甲基化糖醇乙酸酯的检测。
DOI：
10.1016/0003-2697(81)90376-6
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发表时间：
1981
影响因子：
2.9
通讯作者：
Laine,RA
中科院分区：
文献类型：
--
作者：
Laine,RA
化学电离(甲烷)质谱法可以通过去除色谱图中的背景，大大提高中性糖和氨基糖的部分甲基化糖醇乙酸酯的检测灵敏度。通过绘制中性糖衍生物的(MH-60)+离子和氨基糖衍生物的(MH)−离子在每个质量扫描次数下的强度，可以建立有限质量色谱图。每一次甲基被乙酰基取代(意味着糖苷取代的糖)，部分甲基化的糖醇醋酸酯的质量增加28道尔顿。因此，一定取代数的每一组导数都可以由一个高强度的单一离子绘制出来。这些可以单独绘制，显示可以描绘末端、单取代、双取代或更高取代衍生物的质谱图。更有用的是复合多质量色谱图，它提供了样品中所有可能的糖衍生物的完整轮廓，但信噪比大大提高。从称量的已知标准开始，稀释到已知浓度的最终导数，我们可以检测到每个峰低至100pg的可用峰，其中1至10 ng适合常规分析。由于制备步骤中的损失，从未知的糖样品开始制备部分甲基化的阿迪醇乙酸酯需要更多的材料。从5-20μg的低聚糖中可以获得有用的信息。
Chemical ionization (methane) mass spectrometry can be used to greatly enhance the sensitivity of detection of partially methylated alditol acetates of neutral and amino sugars by removing background from gas chromatograms. Limited mass chromatograms can be constructed by plotting the intensity of (MH-60)+ions for neutral sugar derivatives and (MH)−ions for amino sugar derivatives at each mass spectrometric scan number. Each substitution of a methyl with an acetyl group (signifying a glycosidically substituted sugar) increases the mass of the partially methylated alditol acetate by 28 daltons. Therefore, each set of derivatives of a certain substitution number can be plotted by a single ion of high intensity. These can be plotted individually, showing mass chromatograms that can depict terminal, mono-, di-, or higher substituted derivatives. More useful is a composite multiple mass chromatogram giving a complete profile of all possible sugar derivatives in the sample, but with greatly enhanced signal-to-noise ratio. Starting with a weighed amount of known standard and diluting to known concentration of the final derivative, we can detect usable peaks from as little as 100 pg per peak, with 1 to 10 ng suitable for routine analysis. Starting with an unknown sample of saccharide and preparing the partially methylated alditol acetates requires more material, due to losses during preparative steps. Useful information can be gained from 5 to 20 μg of oligosaccharide.