Development of High-throughput Analytical Platforms Based on Chromatographic Techniques Coupled with Mass Spectrometry for the Identification And/or Quantification of Organic Micropollutants And/or Metabolites in Environmental, Food and Clinical Matrices

In an ever-changing world, it is necessary to take into account the incessant exposure that organisms, including humans, have to an ever-increasing number of contaminants of emerging concern (CECs) and their transformation products (TPs), which are often little or not at all known. The risk of this exposure, is often greatly underestimated, and known analytical techniques are often only able to monitor a small part of the growing number of CECs and TPs released into the environment. Year after year, analytical chemistry leads to ever-increasing technological progress in this field. The development of innovative, selective and sensitive methodological approaches is also going hand in hand with the need to find extraction, separation and analysis protocols that can comply with the twelve criteria of Green Analytical Chemistry, highlighting the importance of the environmental sustainability. In this regard, this PhD work aims to develop and optimise sample treatment and subsequent analysis methods that enable the detection and quantification of analytes belonging to different classes (e.g. pharmaceuticals, hormones, microplastics, perfluoroalkyl substances metabolites, and TPs), in both solid and liquid matrices. Some sustainable alternatives are proposed for the development of these methods, such as the use of pressurised hot water for the extraction of pharmaceuticals from soils with different textural characteristics, directly connected to the subsequent chromatographic system. The use of Py-GC-MS, preceded by a microwave-assisted extraction using hydrogen peroxide as a reagent, is a rapid and environmentally friendly procedure that enables the identification and quantification of microplastics in samples of varying complexity. The use of biochar derived from waste material (i.e. sewage sludge) as an absorbent in the d-SPE phase of the QuEChERS protocol is also an environmentally friendly alternative to the expensive commercially available phases. The integration of thermal-assisted desorption with online solid-phase extraction and reversed-phase liquid chromatography for the analysis of polar compounds makes it possible to reduce analysis time and avoid the use of organic solvents for analyte desorption. In this scenario, it becomes necessary to monitor not only CECs, but also their TPs, which are often even more dangerous than the parent ones. Non-target and suspect screening approaches allow the identification of known and unknown compounds within drinking water treatment processes and/or wastewater treatment plants in order to assess their presence, study their degradation pathway and evaluate the abatement capacity of current water treatment systems. Overall, the results obtained highlight the applicability of efficient and increasingly sustainable methodologies for the monitoring and mitigation of CECs in various matrices.