The determination of explosive compounds in solids and liquids is important for forensic and defence monitoring applications such as identification of unexploded residues following a blast, forensic examination of clothing from a suspect or analysis of materials at a crime scene where illicit manufacture or storage is suspected. Furthermore, explosive compounds may find their way into the environment via use in warfare or domestic terrorism, as waste from illicit manufacture or inadvertently as part of legitimate activities. Many explosives cause ecological harm,1 and where contamination of waterways is likely, monitoring should be carried out.
Many relevant sample matrices are highly complex, complicating the determination of explosives at low levels. Currently, liquid–liquid extraction (LLE) and solid-phase extraction (SPE) are commonly used in explosives detection;2,3 however, these techniques are predominantly manual and time-consuming and involve extensive use of expensive and potentially hazardous solvents. Solid-phase microextraction (SPME) is an alternative technique,4,5 but fragile SPME fibers are usually restricted to headspace sampling and limited for trace-level applications by the low phase loading (typically 0.5–1 μL).