Rapid identification and desorption mechanisms of nitrogen-based explosives by ambient micro-fabricated glow discharge plasma desorption/ionization (MFGDP) mass spectrometry.
A novel technique of micro-fabricated glow discharge plasma desorption/ionization mass spectrometry was investigated for the first time in negative ion mode in this study. Negative ion micro-fabricated glow discharge plasma desorption/ionization mass spectrometry (NI-MFGDP-MS) was successfully applied to identify trace explosives in open air. Six explosives and explosives-related compounds were directly analyzed in seconds with this ion source. The ions of [M-H]-were predominant for 2-methyl-1,3,5-trinitrobenzene (trinitrotoluene, TNT) and 2,4,6-trinitrophenol (picric acid), and [M+NO3]-were dominant ions for 1,3,5-trinitro-perhydro-1,3,5-triazine (cyclonite, RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (octogen, HMX), 1,2,3-trinitroxypropane (nitroglycerin, NG), and pentaerythritol tetranitrate (PETN). The limits of detection (LOD) were from 87.5pgmm-2to 0.4 fg mm-2and the relative standard deviation (RSD) ranged between 5.8% and 16.8% for the explosives involved in this study. The reliability of NI-MFGDP-MS was characterized by the analysis of a picric acid-RDX-PETN mixture and a mixture of RDX-pond water. NI-MFGDP-MS and ESI-MS were compared with these explosives and along with collision induced dissociation (CID) experiments. The results showed that electron capture, proton abstraction reaction, nucleophilic attack, ion-molecule attachment, decomposition and anion attachment took place during the NI-MFGDP-MS measurement. These findings provide a guideline and a supplement to the chemical libraries for rapid and accurate detection of explosives. The method shows great potential for fast, in situ, on-line and high throughput detection of explosives in the field of antiterrorism.
Key Laboratory of Bio-resource and Eco-environment Ministry of Education, College of Life Sciences, Research Center of Analytical Instrumentation, Sichuan University, Chengdu 610064, PR China.
CaiYan
C
Tian
Key Laboratory of Bio-resource and Eco-environment Ministry of Education, College of Life Sciences, Research Center of Analytical Instrumentation, Sichuan University, Chengdu 610064, PR China.
JinWei
J
Yin
College of Chemical Engineering, Sichuan University, Chengdu 610064, PR China.
ZhongJun
Z
Zhao
Key Laboratory of Bio-resource and Eco-environment Ministry of Education, College of Life Sciences, Research Center of Analytical Instrumentation, Sichuan University, Chengdu 610064, PR China.
Yinchenxi
Y
Zhang
Key Laboratory of Bio-resource and Eco-environment Ministry of Education, College of Life Sciences, Research Center of Analytical Instrumentation, Sichuan University, Chengdu 610064, PR China. Electronic address: yduan@scu.edu.cn.
YiXiang
Y
Duan
Desorption ionization; Desorption mechanisms; Explosives; Negative ion mode