Detailed NMR analysis of water-soluble organic compounds in size-resolved particulate matter seasonally collected at a suburban site in Prague

Abstract The water-soluble organic compounds (WSOC) in size-resolved summer and winter aerosol collected in a Prague suburban area were analysed by 1H NMR spectroscopy. Advanced analysis of 1H NMR spectra − NMR aerosolomics − was applied, leading to the identification of 73 organic species in total. The compounds were classified into 9 chemical classes according to chemical nature, and possible aerosol sources were discussed, including an association of compounds across different classes according to common source or degradation pathway. A correlation between carbohydrates and trimethylglycine and choline was found in the coarse summer aerosol. Similar distribution profile was observed for several compounds associated to biomass burning in winter series. Multivariate statistical analysis revealed differences in chemical composition between both seasons and identified the main features of the fine and coarse aerosol matter. The group separation according to the season of sample collection was found mainly affected by levoglucosan while the content of carbohydrates in the coarse aerosol fractions impacted the clustering based on the particle size.