Determination of trace level chemical warfare agents in water and slurry samples using hollow fibre-protected liquid-phase microextraction followed by gas chromatography–mass spectrometry

A simple and solvent-minimised sample preparation technique based on hollow fibre-protected liquid-phase microextraction was investigated for the gas chromatography/mass spectrometric analysis of chemical warfare agents in water and slurry samples. The chemical warfare agents included four nerve agents and a blister agent. Parameters such as extraction solvent, salt concentration, stirring speed and extraction time were optimised using spiked deionised water samples. The technique provided a linear range of two orders of magnitude, good repeatability (RSDs < 10%, n = 6), good linearity (r2 ≥ 0.995) and limits of detection (LODs) in the range of 0.02–0.09 μg l−1 (S/N = 3) under full scan mode. The optimised technique was also applied to more complex slurry samples and similar precision (RSD < 15%, n = 3) and limits of detection (0.02–0.2 μg l−1, S/N = 3) were obtained.