Quantification Approaches in Non-Target LC/ESI/HRMS Analysis: An Interlaboratory Comparison.

Nontargeted screening (NTS) utilizing liquid chromatography electrospray ionization high-resolution mass spectrometry (LC/ESI/HRMS) is increasingly used to identify environmental contaminants. Major differences in the ionization efficiency of compounds in ESI/HRMS result in widely varying responses and complicate quantitative analysis. Despite an increasing number of methods for quantification without authentic standards in NTS, the approaches are evaluated on limited and diverse data sets with varying chemical coverage collected on different instruments, complicating an unbiased comparison.

Target and non-target screening of biomarkers in wastewater: towards a unique analytical methodology for sample preparation.

This study aims to optimize a single preparation methodology based on solid-phase extraction (SPE) that could fit both target and non-target screening of organic biomarkers in raw wastewater, allowing the cross-comparison of results obtained from a same dataset. The efficiency of SPE sorbents used alone (HLB) or in combination in a multilayer cartridge was evaluated based on (i) the extraction recovery and matrix effect in environmental samples (surface water and wastewater) for a list of biomarkers (pharmaceuticals, licit and illicit drugs, artificial sweeteners, isoprostanes, polyphenols) and (ii) a number of detected features and their intensity in HRMS. The selected method uses a combination of three SPE sorbents mixed together (HLB, X-AW and X-CW) and seems to take full advantage of each, providing satisfactory validation parameters (recovery, instrumental limit of detection, linearity range and limit of quantification) over a large range of physico-chemical properties while ensuring promising results for non-target screening applications.

Inter-laboratory mass spectrometry dataset based on passive sampling of drinking water for non-target analysis.

Non-target analysis (NTA) employing high-resolution mass spectrometry is a commonly applied approach for the detection of novel chemicals of emerging concern in complex environmental samples. NTA typically results in large and information-rich datasets that require computer aided (ideally automated) strategies for their processing and interpretation. Such strategies do however raise the challenge of reproducibility between and within different processing workflows.