1,4-Benzoquinone as a Highly Efficient Dopant for Enhanced Ionization and Detection of Nitramine Explosives on a Single-
- PDF / 1,240,218 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 117 Downloads / 181 Views
J. Am. Soc. Mass Spectrom. (2019) DOI: 10.1007/s13361-019-02339-8
RESEARCH ARTICLE
1,4-Benzoquinone as a Highly Efficient Dopant for Enhanced Ionization and Detection of Nitramine Explosives on a Single-Quadrupole Mass Spectrometer Fitted with a Helium-Plasma Ionization (HePI) Source Julius Pavlov,1
David Douce,2 Steve Bajic,2 Athula B. Attygalle1
1
Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ 07030, USA 2 Waters Corporation, Wilmslow, UK
Abstract. Previous investigations have evaluated the efficacy of anions such as NO3−, Cl−, Br−, CH3COO−, and CF3COO− as additives to generate or enhance mass spectrometric signals from explosives under plasma ionization conditions. The results of this study demonstrate that for detecting nitramine-class explosives, such as 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX), 1,4-benzoquinone (BQ) is a highly effective and efficient dopant. When used in conjunction with ambient-pressure negative-ion helium-plasma ionization (HePI), 1,4-benzoquinone readily captures an electron, forming an abundant molecular anion (m/z 108), which upon exposure to vapors of RDX and HMX generates adduct ions of m/z 330 and 404, respectively. The signal level recorded for RDX upon adduction to the radical anion of 1,4-benzoquinone under our experimental conditions was significantly higher than that realized by chloride adduction using dichloromethane (DCM) as the dopant. Keywords: 1,4-Benzoquinone, Nitramine explosives, Ambient mass spectrometry, Ionization methods, Gasphase adducts, Electron-capture ionization Received: 23 July 2019/Revised: 4 September 2019/Accepted: 9 September 2019
Introduction
T
he marked rise in terrorist activities involving explosive devices has driven the interest in developing highperforming and portable analytical systems that enable the rapid, reliable, sensitive, and specific detection of energetic materials. Thus, the timely detection of explosives in the laboratory and, preferably, in the field has become a vital task to perform in order to protect society from terrorism [1, 2]. In
Electronic supplementary material The online version of this article (https:// doi.org/10.1007/s13361-019-02339-8) contains supplementary material, which is available to authorized users. Correspondence to: Athula Attygalle; e-mail: [email protected]
addition, explosives enter the atmosphere, water, and soil through military activities. Therefore, analytical chemists are challenged with the detection of post-explosion residues and the identification of traces of explosives on the bodies and clothing of suspects, and with monitoring effluents from munitions plants. A plethora of methods already exists for the detection of explosives [3, 4]. Among the available analytical methods, ion mobility spectrometry (IMS), which delivers lownanogram-level detection, is one of the most widely used [5]. However, IMS is a low-resolution method that tends to yield
Data Loading...
