title: Optimization of headspace solid-phase microextraction technique for extraction of volatile smokeless powder compounds in forensic applications.
abstract: Smokeless powders are low explosives and are potentially found in cases involving firearms and improvised explosive devices. Apart from inorganic compound analysis, forensic determination of organic components of these materials appears as a promising alternative, especially the chromatographic techniques. This work describes the optimization of a solid-phase microextraction technique using an 85 μm polyacrylate fiber followed by gas chromatography-flame ionization detection for smokeless powder. A multivariate experimental design was performed to optimize extraction-influencing parameters. A 2(4) factorial first-order design revealed that sample temperature and extraction time were the major influencing parameters. Doehlert matrix design has subsequently selected 66°C and 21 min as the compromised conditions for the two predetermined parameters. This extraction technique has successfully detected the headspace compounds of smokeless powders from different ammunition types and allowed for their differentiation. The novel technique allows more rapid sample preparation for chromatographic detection of smokeless powders.
authors.affiliation: Forensic Science Program, School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, 16150, Kelantan, Malaysia.
authors.forename: Kah Haw
authors.initials: KH
authors.lastname: Chang
authors.forename: Chong Hooi
authors.initials: CH
authors.lastname: Yew
authors.forename: Ahmad Fahmi Lim
authors.initials: AF
authors.lastname: Abdullah
keywords: Doehlert matrix design; forensic chemistry; forensic science; gas chromatography-flame ionization detection; multivariate experimental design; smokeless powders; solid-phase microextraction