Fast Gas Chromatography of Explosive Compounds Using a Pulsed-Discharge Electron Capture Detector

• NCJ Number: 215146
• Journal: Journal of Forensic Sciences Volume: 51 Issue: 4 Dated: July 2006 Pages: 815-818
• Author(s): Olivier L. Collin B.Sc.; Claudia Niegel; Kate E. DeRhodes; Bruce R. McCord Ph.D.; Glen P. Jackson Ph.D.
• Date Published: July 2006
• Length: 4 pages
• Grant Number(s): DAAD05-02-C-0035
• Sponsoring Agency: U.S. Technical Support Working Group (TSWG); Ohio University Provost Undergraduate Research Fund
• Publication Format: Article
• Publication Type: Report (Technical); Report (Study/Research)
• Language: English
• Country: United States of America

Annotation

The experiment described in this paper used a combination of a new, nonradioactive pulsed-discharge electron capture detector (PDECD) with a microbore gas chromatography (GC) column to achieve fast separation times and low detection limits for the analysis of nine common explosives and related compounds.

Abstract

The results show that the PDECD is a suitable detector of explosives when used in combination with fast GC. The main improvements described in this paper are the combination of the PDECD with a microbore column and the reduction in the analysis time to less than 2.5 minutes for the mixtures of the nine explosives compounds studied. The fast separation time limits on-column degradation of the thermally labile compounds and decreases the peak widths; this results in larger peak intensities and a resulting improvement in detection limits (between 5 and 72 fg for the nine explosives studied). The combination of short analysis time and low detection limits makes this method a potential candidate for screening large numbers of samples that have been prepared with techniques such as liquid-liquid extraction or solid-phase microextraction. Another potential advantage of the PDECD that has yet to be examined is the control of the distribution of kinetic energy of the electrons in the source by changing the nature of the dopant gas. This capability might allow improved selectivity of nitro-containing compounds over halogenated compounds, which could eliminate some of the interferences in the study of real-life samples. The sensitivity of the detector for the explosive might also be improved in a similar manner. The nine explosive compounds included nitrate esters, nitroaromatics, and a nitramine. Compared to the standard ECD, the PDECD uses a pulsed plasma to generate the standing electron current instead of a radioactive source. 1 table, 2 figures, and 29 references