New Techniques and Methods in Explosive Analysis

In forensic analytical chemistry, chemical investigation of the liquid/gas/solid evidences from the crime scene after the explosion (soil, water, concrete/glass/ wood pieces, metal, clothes taken from suspects, etc.) and reliable identification of explosive residues on such evidences remain an active area of research due to increased demand for homeland security against terrorist and warfare threats, as well as environmental monitoring. GC-MS, LC-MS, and LC-MS/MS offer distinct advantages for laboratory analysis of explosives in post-blast samples, including soil/ water/plant matrices, etc. Time-of-Flight, Ion-Trap, and Orbitrap technologies provide high resolution, better analyte identification, and accurate mass information at sub-ppm levels. Direct analysis techniques, such as ambient MS has a wider range of applications and offer high sensitivity/selectivity and direct analysis from the surface of interest. Techniques like Direct Analysis In Real Time (DART) and Desorption electrospray ionization (DESI), which can ionize substances directly on surfaces, offer new opportunities for security screening of explosives. Orbitrap MS was also used together with Raman microscopy for detailed molecular-level characterization of explosives and the chemical analysis of latent fingerprints. Electro-flow focusing ionization with in-source collision-induced dissociation can be used for MS detection and chemical imaging for speciation of the signatures of explosive devices and to detect proper spatial discrimination of explosive traces. Miniaturization to be used infield analysis with low cost is a technique work on currently. Multi-analyte detection with high selectivity/sensitivity to be able to use in as many different matrices and to be able to analyze without or with a very short and simple sample preparation methods are targeted for future analyses. Despite other reviews focussing on a certain group of techniques, this chapter summarizes some important developments in the standard MS techniques and ambient MS techniques used in laboratory, on-site, and miniaturized mass spectrometric analysis of high energetic materials in the last two decades, mostly conducted in the last decade.

Keywords: Ambient Mass Spectrometry, Confirmation, DART-MS, DESI-MS Imaging, Determination, Energetic Materials, Explosive Analysis, GC-MS, Hyphenated Techniques, Identification, Ion Trap, LCMS/MS, Mass Spectrometry (MS), Multi- Analyte Screening, On-site detection, Quantitation Methods, Recent Technologies, ToFMS, Terrorism, Triple Quadrupole, Validation.