Analysis of nitroaromatic compounds in complex samples using solid-phase microextraction and isotope dilution quantification gas chromatography–electron-capture negative ionisation mass spectrometry

A solid-phase microextraction (SPME) method using gas chromatography–electron-capture negative ionisation mass spectrometry (GC–ECNI-MS) and isotope dilution quantification for the analysis of nitroaromatic compounds in complex, water based samples has been optimised. For ionisation, ECNI was the most sensitive and selective method. SPME was compared to solid-phase extraction (SPE) and found to be more sensitive for these small volume samples. LODs were in the range 0.02–38 ng L−1 for SPME and 6–184 ng L−1 for SPE, respectively. The SPME method was applied on samples in the ng L−1 level from artificial reed beds treated with sludge containing residues from explosives and pharmaceuticals.