Free amino acids in aerosol samples collected over the central Arctic Ocean in summer
(English)Manuscript (preprint) (Other academic)
Size-resolved airborne particle samples collected over the central Arctic Ocean in summer, during the Arctic Ocean expedition (AOE)-2001, have with regard to dissolved free amino acids (DFAAs) been analysed. Serine, alanine, aspartic acid followed by glutamatic acid was the dominating amino acids in the DFAA fraction. The high concentrations of serine found in all blanks must be taken into consider discussing its contribution. The total concentration of DFAAs in the bulk aerosols, with serine excluded ranged from 13-89 pmol/m3, which agree well with previous less size-resolved data reported for remote areas. The DFAA fraction was shown to explain <0.7% of the total particle mass collected on the substrate. The size distribution of the DFAAs showed enrichment towards the submicron mode with a factor of 2-3 compare to the coarse mode. As the DFAAs were found in sizes corresponding to either film or jet drops, or to both, the surface micro layer was suggested to be their source. A comparison of the reported DFAA composition with amino acid data obtained for simultaneously collected micro layer samples, showed no clear relation. Ongoing oxidation of proteins and peptides on the sampling substrate combined with the considerable variation of the amino acid composition in the microlayer over time and sampling site may explain the obtained differences.
Meteorology and Atmospheric Sciences
Research subject Applied Environmental Science
IdentifiersURN: urn:nbn:se:su:diva-29474OAI: oai:DiVA.org:su-29474DiVA: diva2:233465