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首页> 外文期刊>Journal of applied toxicology >Analysis of the degradation compounds of chemical warfare agents using liquid chromatography/mass spectrometry.
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Analysis of the degradation compounds of chemical warfare agents using liquid chromatography/mass spectrometry.

机译：使用液相色谱/质谱法分析化学战剂的降解化合物。

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The analysis of the degradation products of chemical warfare (CW) agents has been a challenge to analysts. The low volatility of these compounds makes them unsuitable for direct gas chromatography analysis without prior derivatization. Lack of a chromophore causes difficulties with classic detection methods after liquid chromatography separation. With the recent development of various interfaces that allow for the introduction of a liquid solvent stream into the mass spectrometer, the task of directly analyzing these compounds has become easier. For this report, we examined three different liquid chromatography/mass spectrometry (LC/MS) interfaces for their suitability for the analysis of CW degradation compounds. The interface types examined were particle beam electron impact ionization (PBI), electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI). Several alkylphosphonates and thiodiglycol analogs that are produced from the degradation of organophosphorus nerve agents and sulfur mustard, respectively, were analyzed using each of the three techniques. Electron impact ionization following gas chromatography or particle beam introduction typically generates very reproducible, library-searchable mass spectra. Most of the CW breakdown compounds examined using the PBI interface did not produce a molecular ion. Despite the lack of a molecular ion, the mass spectra of the various compounds contained enough different structural information from fragment ions for the positive identification of each. The mass spectra generated using ESI are generally limited to protonated molecular ions with little or no fragmentation. For positive identification and confirmation, tandem mass spectrometry techniques quite often must be used. Many of the compounds in this study were characterized by prominent sodiated adducts along with the protonated molecular ion. Methylphosphonic acid produced protonated dimers, trimers, etc. Although the various adduct ions can be used for additional confirmation of the molecular weight of a compound, the adducts also can result in suppression of ionization of the compound and thus reduce sensitivity. Another 'soft' ionization technique that results in abundant protonated molecular ions is APCI. The mass spectra of the breakdown compounds produced using APCI were characterized generally by either a prominent protonated molecular ion or a dehydrated form of it. In addition, a number of structurally significant fragment ions were observed and their relative abundances could be adjusted by altering the APCI conditions. The data presented here indicate that each of the three techniques can be used successfully for direct liquid introduction and analysis of the non-volatile compounds produced from the degradation of CW agents. The mass spectra produced using each technique are quite different and could be utilized as additional confirmation of compound identity. Copyright 2001 John Wiley & Sons, Ltd.
机译：化学战剂降解产物的分析一直是分析人员的挑战。这些化合物的挥发性低，因此不适合直接进行气相色谱分析而无需事先衍生化。发色团的缺乏导致液相色谱分离后传统检测方法的困难。随着各种接口的最新发展，这些接口允许将液体溶剂流引入质谱仪，直接分析这些化合物的任务变得更加容易。对于本报告，我们检查了三种不同的液相色谱/质谱（LC / MS）接口，以适合分析CW降解化合物。检验的界面类型为粒子束电子碰撞电离（PBI），电喷雾电离（ESI）和大气压化学电离（APCI）。使用这三种技术分别分析了分别由有机磷神经毒剂和硫芥子降解产生的几种烷基膦酸酯和硫代二甘醇类似物。气相色谱法或引入粒子束之后的电子碰撞电离通常会产生可重现的，可在谱库中搜索的质谱图。使用PBI界面检查的大多数CW分解化合物都不会产生分子离子。尽管缺少分子离子，但各种化合物的质谱图都包含来自碎片离子的足够不同的结构信息，用于每种化合物的阳性鉴定。使用ESI生成的质谱图通常限于质子化的分子离子，很少或没有碎片。为了进行积极的鉴定和确认，必须经常使用串联质谱技术。在这项研究中，许多化合物的特征是明显的磺化加合物以及质子化的分子离子。甲基膦酸可生成质子化的二聚体，三聚体等。尽管各种加合物离子可用于进一步确认化合物的分子量，但这些加合物也可导致抑制化合物的电离并因此降低灵敏度。导致大量质子化分子离子的另一种“软”电离技术是APCI。使用APCI生产的分解化合物的质谱图通常通过突出的质子化分子离子或脱水形式表征。此外，观察到许多结构上重要的碎片离子，可以通过改变APCI条件来调节其相对丰度。此处提供的数据表明，三种技术中的每一种均可成功用于直接液体引入和分析由CW试剂降解产生的非挥发性化合物。使用每种技术产生的质谱图完全不同，可以用作化合物同一性的其他确认。版权所有2001 John Wiley＆Sons，Ltd.

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