C2Cl6掺杂剂辅助离子迁移谱研究不同材料表面激光解吸爆炸物

来源: Emanuel Maťaš et al 发布日期: 2024-09-23 访问量: 19

导读	种高效、灵敏的激光解吸取样离子迁移谱（IMS）系统被应用于使用不同表面材料的快速爆炸物检测。这种便携式智能检测系统探测器由电池供电，具有移动性，适合在野外或战区使用标签: 离子迁移谱、爆炸物、六氯乙烷、掺杂剂、IMS、PAIMS

Laser Desorption of Explosives from the Surface of Different Real-World Materials Studied Using C2Cl6-Dopant-Assisted Ion Mobility Spectrometry
Emanuel Maťaš ¹,Matej Petrík²,Martin Sabo ^2,3 Štefan Matejčík¹,*
¹Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, 842 48 Bratislava, Slovakia
²Faculty of Informatics and Information Technologies, Slovak University of Technology in Bratislava, 842 16 Bratislava, Slovakia
³MaSa Tech s.r.o., Sadová 3018/10, 916 01 Stará Turá, Slovakia
*
Author to whom correspondence should be addressed.
Molecules 2024, 29(18), 4482; https://doi.org/10.3390/molecules29184482 (registering DOI)
Submission received: 7 August 2024 / Revised: 7 September 2024 / Accepted: 9 September 2024 / Published: 21 September 2024

Abstract

A highly efficient and sensitive ion mobility spectrometry (IMS) system with laser desorption sampling was applied for rapid explosive detection using different surface materials. This portable IMS detector, powered by a battery, offers mobility and is suitable for use in the field or combat zones. The laser desorption (LD) sampling of common explosives (Trinitrotoluene—TNT; Dinitrotoluenes—DNTs; Hexogene—RDX; pentaerythritol tetranitrate—PETN; plastic explosives—Compound 4 (C-4) and Semtex) on a wide range of common surface materials, such as metal, ceramic, plastic, glass, drywall, paper, wood, and textiles, was studied. Successful detection was achieved on nearly all surfaces except flammable materials (paper, wood, and textiles). The limit of detection (LOD) was determined for each explosive and specific surface, demonstrating an impressive LOD of 7 ng/mm2 for TNT. RDX, C-4, PETN, and Semtex achieved LOD values of 15 ng/mm2, while DNTs showed an LOD of approximately 50 ng/mm2.

一种高效、灵敏的激光解吸取样离子迁移谱（IMS）系统被应用于使用不同表面材料的快速爆炸物检测。这种便携式智能检测系统探测器由电池供电，具有移动性，适合在野外或战区使用。研究了在金属、陶瓷、塑料、玻璃、石膏板、纸张、木材和纺织品等多种常见表面材料上对常见爆炸物（三硝基甲苯-TNT、二硝基甲苯-DNT、己烯-RDX、季戊四醇四硝酸酯-PETN、塑料爆炸物化合物4（C-4）和Semtex）的激光解吸（LD）取样。除了易燃材料（纸张、木材和纺织品）外，几乎所有表面都实现了成功检测。确定了每种炸药和比表面积的检测限（LOD），TNT的检测限为7 ng/mm2，令人印象深刻。RDX、C-4、PETN和Semtex的检出限值为15 ng/mm2，而DNT的检出限约为50 ng/mm2。

Keywords: ion mobility spectroscopy; explosive detection; laser desorption; trace analysis; security checkpoint

3. Materials and Methods
3.1. Experimental Setup
The ion mobility spectrometry (IMS) system used in this study to detect explosives was developed by MaSa Tech Ltd., Company (Stará Turá, Slovakia). The IMS device was boxed with all electronics, power supplies, filters, and dopant gas (Figure 4a). The device was powered by a battery that allowed continuous operation for up to 8 h. This makes the IMS a highly portable analytical device. The IMS instrument was constructed using multiple stainless-steel ring electrodes isolated by Teflon rings, resulting in a total length of the drift tube of 11.16 cm, as shown in Figure 4b. The corona discharge (CD) ionization source was operated in negative polarity, following a point-to-plane geometry, with the gas outlet positioned behind the discharge, allowing the CD to operate in a reverse-flow regime. For IMS equipment, a Bradbury–Nielsen-type shutter grid (SG) with an opening time of 150 µs and a period of 14,500 µs was employed. A potential difference of 3.6 kV was applied across the CD, and the electric field intensity inside the drift tube was set to 509.8 V.cm−1. As a drift gas was used, purified atmospheric air was obtained through a zeolite filter (Agilent Technologies, Inc., Santa Clara, CA, USA) with a typical flow rate of 600 mL/min. The operational pressure was maintained at 600 mbar, and the IMS drift tube temperature was set to 60 °C. The desorbed sample was sucked through a 50 cm long PEEK capillary with an inner diameter of 0.8 mm. The sample gas flow comprised 500 mL/min of atmospheric air without additional purification but with an admixture of C2Cl6 dopant with a concentration of 750 ppb. The capillary input was positioned perpendicular to the laser beam, several millimeters from the sample surface. A standard diode laser operating at a wavelength of 532 nm (green light) with a power of 1000 mW was employed in the setup. The spot of the focused laser beam was 1.4 mm2. The irradiation time was exactly one second for all measurements.

Figure 4. (a) Storage of the IMS instrument in a transport box with electronics, battery, flow system, and laser; (b) scheme of IMS with dopant gas C₂Cl₆ and laser.