NRC Post-Doctoral Fellow at US Naval Research Laboratory Washington, D.C., USA.
Chemistry Division, US Naval Research Laboratory Washington, D.C., USA.
J Chromatogr A. 2019 Oct 11;1603:407-411. doi: 10.1016/j.chroma.2019.05.029. Epub 2019 May 15.
The development of an online sampling method using programmable temperature vaporization gas chromatography with a mass spectrometer detector (PTV-GC/MS) for the analysis of trace pentaerythritol tetranitrate (PETN) vapor is presented. PETN degradation was minimized by optimizing the temperature and flow rates of the vapor sampling infrastructure. Validation of the online method was done using a previously published technique, vapor sampling with Tenax-TA thermal desorption tubes followed by analysis with a thermal desorption system coupled to a programmable temperature vaporization gas chromatograph with a micro-electron capture detector (TDS-PTV-GC/μECD). Trace PETN vapor was generated using state-of-the-art instrumentation known as the TESTbed, located at the US Naval Research Laboratory. For PETN vapor concentrations in the parts per trillion (ppt) range, quantitative results from the TDS-PTV-GC/μECD consistently showed concentrations approximately double that measured by the online PTV-GC/MS method, indicating that sample loss due to additional exposure to the vapor sampling infrastructure occurs when using online sampling. Further utilization of the online PTV-GC/MS system allowed for the quantitation/semi-quantitation of PETN vapor concentrations as low as 260 parts per quadrillion (ppq) with only 10 min of sampling time.
介绍了一种使用程序升温汽化气相色谱-质谱联用仪（PTV-GC/MS）分析痕量季戊四醇四硝酸酯（PETN）蒸气的在线采样方法的开发。通过优化蒸气采样基础设施的温度和流速，最大限度地减少了 PETN 的降解。使用先前发表的技术，即 Tenax-TA 热解吸管蒸气采样，然后与热解吸系统耦合，用程序升温汽化气相色谱-微电子俘获检测器（TDS-PTV-GC/μECD）进行分析，对在线方法进行了验证。使用位于美国海军研究实验室的称为 TESTbed 的最先进仪器产生痕量 PETN 蒸气。对于在万亿分之几（ppt）范围内的 PETN 蒸气浓度，TDS-PTV-GC/μECD 的定量结果始终显示出比在线 PTV-GC/MS 方法测量的浓度约高两倍，这表明在使用在线采样时，由于对蒸气采样基础设施的额外暴露，会导致样品损失。进一步利用在线 PTV-GC/MS 系统，仅需 10 分钟的采样时间，即可对 PETN 蒸气浓度进行定量/半定量分析，低至 260 万亿分率（ppq）。
