The investigation of clandestine laboratories poses serious hazards for first responders, emergency services, investigators and the surrounding public due to the risk of exposure to volatile organic compounds (VOCs) used in the manufacture of illicit substances. A novel gas sampling interface using open microfluidic channels that enables the extraction of VOCs out of the gas phase and into a liquid, where it can be analysed by conventional detection systems, has recently been developed. This paper investigates the efficiency and effectiveness of such a gas-to-liquid (GTL) extraction system for the extraction of amphetamine-type substances (ATS) and their precursors from the vapour phase. The GTL interface was evaluated across a range of different ATS and their precursors (methamphetamine, dimethylamphetamine, N-formylmethamphetamine, benzaldehyde, phenyl-2-propanone, ephedrine and pseudoephedrine) at concentrations ranging between 10 and 32 mg m⁻³. These gas samples were produced by a gas generation system directly in Tedlar^® bags and gas canisters for controlled volume sampling. When using gas sampled from Tedlar^® bags, four of the seven compounds were able to be extracted by the GTL interface, with the majority of the VOCs having extraction yields between 0.005% and 4.5%, in line with the results from an initial study. When samples were taken from gas canisters, only benzaldehyde was able to be detected, with extraction efficiencies between 0.2% and 0.4%. A custom-built mount for the GTL interface helped to automate the extraction process, with the aim of increasing extraction efficiency or reducing variability. However, the extraction efficiency did not improve when using this accessory, but the procedure did become more efficient. The results from the study indicated that the GTL interface could be employed for the collection of gaseous ATS and incorporated into mobile detection systems for onsite collection and analysis of volatile compounds related to ATS manufacture.

中文翻译：

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应用微流体气液界面从空气样品中提取目标苯丙胺和前体

对秘密实验室的调查对急救人员，紧急服务人员，调查人员和周围的公众构成严重危害，因为它们可能接触用于制造非法物质的挥发性有机化合物（VOC）。最近已经开发出一种新颖的气体采样接口，该接口使用开放的微流体通道，能够将VOC从气相中提取到液体中，并可以通过常规检测系统对其进行分析。本文研究了从气相中提取苯丙胺类物质（ATS）及其前体的这种气液（GTL）提取系统的效率和有效性。在各种不同的ATS及其前体（甲基苯丙胺，二甲基苯丙胺，N-甲酰基甲基苯丙胺，苯甲醛，⁻³。这些气体样品通过一气体发生系统直接在泰德拉产生^®袋和用于受控体积采样煤气罐。当使用从采样的Tedlar气体^®袋中，可以通过GTL界面提取7种化合物中的4种，而大多数VOC的提取率在0.005％至4.5％之间，这与初步研究的结果一致。从气体罐中采集样品时，仅能检测到苯甲醛，萃取效率在0.2％至0.4％之间。GTL接口的定制安装架有助于实现提取过程的自动化，目的是提高提取效率或减少变化。但是，使用该附件时，提取效率并未提高，但过程确实变得更加有效。