DART-MS Spectral Similarity of Infrared Thermally Desorbed Solid Particulate and Solution Cast Propellant Samples

Area of Science:

• Forensic Science
• Analytical Chemistry
• Materials Science

Background:

• Security and forensic applications rely on test materials for instrument development and validation.
• Homemade explosives, including pyrotechnics and propellants, are an emerging threat requiring accurate reference materials.
• Precision liquid deposition is a common method for creating trace-level test materials.

Purpose of the Study:

• To investigate mass spectral differences between solid particulate and liquid-deposited propellant samples.
• To compare the chemical signatures of different propellant forms using infrared thermal desorption direct analysis in real time mass spectrometry (IRTD-DART-MS).

Main Methods:

• Infrared thermal desorption direct analysis in real time mass spectrometry (IRTD-DART-MS) was used.
• Solid particulate and solution-cast (liquid-deposited) samples of black powders and substitutes were analyzed.
• Mass spectral data and ion distributions were compared.

Main Results:

• Observable differences in mass spectra and ion distributions were found between solid and liquid-deposited samples.
• These variations are attributed to chemical degradation and physical differences in crystal formation, spatial distribution, morphology, and size.
• The study highlights the impact of sample preparation on analytical results.

Conclusions:

• The physical and chemical properties of test materials significantly influence analytical outcomes.
• Accurate representation of threat materials is critical for developing effective detection technologies.
• Further research into optimizing test material production is essential for advancing forensic analysis and security.