Characterization of human exposome through urine analysis: suitability of sample pretreatment methods for multicomponent target analysis and non-target screening.

Since his first definition in 2005, exposome has been studied from several research groups in both environmental and biological samples. Most of the first works focused on a specific family of compounds and, therefore, methods for target analysis have been developed for years in both environmental and human biofluids for decades. Successively, with the improvement of HRMS techniques, the number of compounds that could be simultaneously determined increased. As consequence, the trend moved from target approaches to suspect and non-target screening with the objective to include the widest possible number of compounds belonging to different families and industrial applications. In this sense, human exposome is still unexplored and many efforts are going in the construction of online databases for further screening applications. The aim of this work was to advance the application of HRMS to urine samples in order to characterize the human exposome. Optimization of experimental parameters was conducted on a multicomponent target list with spiked synthetic urine and then applied to real samples for the SNTS analysis. The presented Master thesis will therefore develop the following methodological objetives: 1. Development of a chromatographic method for the simultaneous determination of 220 compounds, defining the injection and elution conditions in UHPLC-HESI-HRMS/MS. 2. Optimization of sample treatment procedures, with specific focus on LLE and D&S, for the target analysis of 220 compounds (PFAS, parabens, phthalates, benzophenones, biocides, pharmaceutical and industrial chemicals) and application of SPE from a previous work. 3. Definition of instrumental and procedural LOQs and LOIs and evaluation of analytical performances obtained with the three methods in terms of recoveries and matrix effect. 4. Target and SNTS analysis of real urine samples to highlight the differences between pretreatment methods in terms of the number of compounds detected and identified. 5. Definition of the method that results more suitable for application in this field, and further steps in method validation