State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, China.
State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, China.
Talanta. 2018 Feb 1;178:636-643. doi: 10.1016/j.talanta.2017.09.088. Epub 2017 Oct 2.
Many organic amines that comprise a benzene ring are policy-sensitive because of their toxicity and links to social harm. However, to date, detection of such compounds mainly relies on offline methods. This study proposes an online pptv (parts per trillion by volume) level of detection method for amines, using the recently-built vacuum ultraviolet photoionization mass spectrometer (VUV-PIMS) combined with a new doping technique. Thus, the dichloromethane doping-assisted photoionization mass spectra of aniline, benzylamine, phenethylamine, amphetamine, and their structural isomers were recorded. The dominant characteristic mass peaks for all amines are those afforded by protonated amines and the amino radical-loss. The signal intensities of the amines were enhanced by 60-130 times compared to those recorded without doping assistance. Under 10s detection time, the sensitivities of aniline and benzylamine in the gas phase were determined as 4.0 and 2.7 countspptv, with limits of detection (LODs) of 36 and 22 pptv, respectively. Notably, the detection efficiency of this method can be tenfold better in future applications since the ion transmission efficiency of the mass spectrometer was intentionally reduced to ~ 10% in this study. Therefore, dichloromethane doping-assisted photoionization mass spectrometry has proven to be a highly promising on-line approach to amine detection in environmental and judicial supervision and shows great potential for application in the biological field.
许多包含苯环的有机胺由于其毒性和与社会危害的关联而成为政策敏感物质。然而，迄今为止，这些化合物的检测主要依赖于离线方法。本研究提出了一种在线 pptv（体积每万亿分率）水平的胺检测方法，使用最近构建的真空紫外光电离质谱仪（VUV-PIMS）结合一种新的掺杂技术。因此，记录了苯胺、苄胺、苯乙胺、苯丙胺及其结构异构体的二氯甲烷掺杂辅助光致电离质谱。所有胺的主要特征质量峰是质子化胺和氨基自由基损失提供的峰。与没有掺杂辅助时记录的谱图相比，胺的信号强度增强了 60-130 倍。在 10 秒的检测时间内，气相中苯胺和苄胺的灵敏度分别确定为 4.0 和 2.7 计数 pptv，检测限（LOD）分别为 36 和 22 pptv。值得注意的是，由于在本研究中故意将质谱的离子传输效率降低到约 10%，因此该方法的检测效率在未来的应用中可以提高十倍。因此，二氯甲烷掺杂辅助光致电离质谱已被证明是一种很有前途的在线方法，可用于环境和司法监管中的胺检测，并显示出在生物领域应用的巨大潜力。
