In Situ Explosive Detection Using a Miniature Plasma Ion Source and a Portable Mass Spectrometer

• Published in: Analytical letters Vol. 45; no. 11; pp. 1440 - 1446
• Main Authors: Dalgleish, Jon K., Hou, Keyong, Ouyang, Zheng, Cooks, R. Graham
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Taylor & Francis Group 15-07-2012; Taylor & Francis
• Subjects: Ambient ionization; Analytical chemistry; Chemistry; Exact sciences and technology; Explosives; Low-temperature plasma; Miniature mass spectrometer; Spectrometric and optical methods; Plasma; In situ; Glass; Ambient ionization; Probe; Plasma sources; Optimization; Molecules; Signal; Hexogen; Low temperature; Trace analysis; Miniature mass spectrometer; Ion source; Pesticides; Pentaerythritol tetranitrate; Air; Herbicide; Ionization; Portable equipment; Explosives; Low-temperature plasma; Detection; Mass spectrometry; Diaphragm pump
• ISSN: 0003-2719; 1532-236X
• DOI: 10.1080/00032719.2012.675485

A small low-temperature plasma (LTP) ionization probe was coupled to a portable mass spectrometer for the rapid detection of trace explosives on surfaces. Using only a small diaphragm pump to supply ambient air to the LTP source, 100 ng each of pentaerythritol tetranitrate (PETN), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), and 2,4,6-trinitrophenylmethylnitramine (Tetryl) were detectable on glass in under 1 minute. The main ion signal from these molecules (M) is the [M + NO
3
]
−
species. While much optimization remains, it is believed that this miniature LTP source will remove the need for external gas cylinders and additional heating for in situ explosives detection using portable mass spectrometers.