Improved prioritisation and fragmentation improve the identification of unknown substances with non-target screening

Non-target screening (NTS) is based on the combination of liquid chromatography in conjunction with high-resolution mass spectrometry (HRMS). In addition, tailored data analysis, with target and suspect screening, are important ways of identifying substances in drinking water and the sources of that water, and of conducting temporal and spatial analyses. Nevertheless, the identity of a large number of substances remains unknown.

The current NTS approach consists of matching the accurate masses (derived from the MS1 spectra, the full scan) and the fragmentation spectrums (MS2) of an unknown feature with the spectra in one or more databases. Fragmentation spectrums are indispensable for substance identification but they are often of poor quality or absent because only a limited number of features can be fragmented during the analysis. The overall goal of this project is to address the limits of non-target screening (NTS) and to improve the identification of organic micropollutants in water samples by developing mass-spectrometry acquisition methods.

The different strategies have proven promising for water research and monitoring, and they allow for the successful privatisation of potentially toxic substances. Background ions were also reduced to generate more accurate results. This extension widens the application possibilities by using different fragmentation techniques.