Sequential window acquisition of all theoretical fragments versus information dependent acquisition for suspected-screening of pharmaceuticals in sediments and mussels by ultra-high pressure liquid chromatography-quadrupole time-of-flight-mass spectrometry

The aquatic ecosystems are dynamic environments often affected directly or indirectly by a myriad of anthropogenic contaminants that need to be properly identified. In this study, liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QqTOF-MS) suspected-screening was applied to mussels and riverine sediment both, non-spiked and spiked with a mixture of 32 pharmaceuticals. Three data acquisition methods -sequential window acquisition of all theoretical fragment-ion spectra (SWATH), in fix (FSWATH) and variable (VSWATH) window modes and Information Dependent Acquisition (IDA)- were compared to determine the most suitable acquisition technique. The results obtained in the spiked samples showed that the two SWATH modes enable to obtain the MS/MS spectrum of a higher number of compounds (up to 27 with FSWATH and 25 with VSWATH) than IDA (up to 19) in sediment and mussel. The different data acquisition modes were also tested in non-spiked samples to verify the results obtained in the spiked ones. Importantly, all the methods are able to detect the MS/MS spectrum of several contaminants in the samples when analysed against a database of >600 compounds. Up to 7 contaminants were tentatively detected with IDA, 15 with FSWATH and 17 with VSWATH. Most pollutants were pesticides and pharmaceuticals, being of particular interest the presence of ibuprofen and acetaminophen in mussels. (C) 2019 Elsevier B.V. All rights reserved.