Membrane assisted solvent extraction coupled to large volume injection-gas chromatography–mass spectrometry for trace analysis of synthetic musks in environmental water samples

This work describes the optimisation, validation and application of membrane assisted solvent extraction (MASE) together with a large volume injection (LVI) in a programmable temperature vaporisation (PTV) injector coupled to gas chromatography–mass spectrometry (GC–MS) for the quantification of ten synthetic musk fragrances (musks) in surface and wastewater samples. Regarding the MASE, musks were extracted from 150 mL of aqueous samples to 200 μL of n-hexane hold in home-made low density polyethylene (LDPE) bags. The extraction took 240 min and the performance of the method made possible the direct analysis of the extracts by LVI-PTV-GC–MS without needing any further treatment and avoiding losses of analytes. During the optimisation of LVI-PTV set-up, the response surfaces of every analyte signal against the cryo-focussing temperature, injection speed and vent time were built. Finally, the figures of merit of the whole procedure allowed the analysis of most of the musks owing to the low method detection limits (between 4 and 25 ng L−1) and good precisions (<20%). In fact, this method was successfully applied to the analysis of musks in surface and wastewater samples. Galaxolide and tonalide are the main two synthetic musks observed in most of the analysed environmental water samples.

► A new MASE-LVI-PTV-GC–MS method was developed to determine musks in waters.
► All the factors affecting the whole procedure were assessed and optimised.
► The analytes were detected in the very low ng L−1 range using only 150 mL of water.
► Matrix effect was evaluated and overcome with deuterated analogues in real samples.
► The developed method was applied to estuarine and wastewater water samples.