Pacific Northwest National Laboratory , 902 Battelle Boulevard, Richland, Washington 99352, United States.
Anal Chem. 2016 May 17;88(10):5406-13. doi: 10.1021/acs.analchem.6b00766. Epub 2016 May 4.
Chemical attribution signatures (CAS) are being investigated for the sourcing of chemical warfare (CW) agents and their starting materials that may be implicated in chemical attacks or CW proliferation. The work reported here demonstrates for the first time trace impurities from the synthesis of tris(2-chloroethyl)amine (HN3) that point to the reagent and the specific reagent stocks used in the synthesis of this CW agent. Thirty batches of HN3 were synthesized using different combinations of commercial stocks of triethanolamine (TEA), thionyl chloride, chloroform, and acetone. The HN3 batches and reagent stocks were then analyzed for impurities by gas chromatography/mass spectrometry. All the reagent stocks had impurity profiles that differentiated them from one another. This was demonstrated by building classification models with partial least-squares discriminant analysis (PLSDA) and obtaining average stock classification errors of 2.4, 2.8, 2.8, and 11% by cross-validation for chloroform (7 stocks), thionyl chloride (3 stocks), acetone (7 stocks), and TEA (3 stocks), respectively, and 0% for a validation set of chloroform samples. In addition, some reagent impurities indicative of reagent type were found in the HN3 batches that were originally present in the reagent stocks and presumably not altered during synthesis. More intriguing, impurities in HN3 batches that were apparently produced by side reactions of impurities unique to specific TEA and chloroform stocks, and thus indicative of their use, were observed.
化学归因特征（CAS）正在被研究用于确定化学战剂及其起始原料的来源，这些化学战剂及其起始原料可能涉及化学袭击或化学战剂的扩散。这里报告的工作首次证明了三（2-氯乙基）胺（HN3）合成过程中的痕量杂质可以指向该化学战剂合成中使用的试剂和特定试剂库存。使用不同组合的三乙醇胺（TEA）、氯化亚砜、氯仿和丙酮的商业库存合成了 30 批 HN3。然后通过气相色谱/质谱法对 HN3 批次和试剂库存进行杂质分析。所有的试剂库存都有各自的杂质特征，可以将它们彼此区分开来。这是通过使用偏最小二乘判别分析（PLSDA）构建分类模型来证明的，对于氯仿（7 个库存）、氯化亚砜（3 个库存）、丙酮（7 个库存）和 TEA（3 个库存），通过交叉验证分别获得了平均库存分类错误率为 2.4%、2.8%、2.8%和 11%，而对于氯仿样品的验证集则为 0%。此外，在最初存在于试剂库存中的 HN3 批次中发现了一些表明试剂类型的试剂杂质，据推测，这些杂质在合成过程中没有发生变化。更有趣的是，在 HN3 批次中观察到了明显由特定 TEA 和氯仿库存中特有的杂质的副反应产生的杂质，因此可以表明它们的使用。
