Simultaneous measurements of free amino acids in seawater, size-segregated aerosol particle and cloud water samples at the Cape Verde Atmospheric Observatory

Simultaneous measurements of free amino acids in seawater (underlying water, ULW, and sea surface microlyer, SML), size-segregated aerosol particle and cloud water samples at the Cape Verde Atmospheric Observatory (CVAO) in the framework of the MarParCloud project with contribution of MARSU in September/October 2017. During this campaign, sampling of size-segregated aerosol particles at the CVAO (30 m sampling tower) and seawater sampling at the ocean site (~16°53ˈ30ˈN, ~24°54ˈ00ˈˈW) were performed. Additionally, aerosol sampler and cloud water sampler were installed at the mountain station on the top of the mountain 'Monte Verde (MV)' (744 m a.s.l.). The amino acid analysis includes glycine (Gly), L-alanine (Ala), L-serine (Ser), L-glutamic acid (Glu), L-threonine (Thr), L-proline (Pro), L-tyrosine (Tyr), L-valine (Val), L-phenylalanine (Phe), L-aspartic acid (Asp), L-isoleucine (Ile), L-leucine (Leu), L-methionine (Met), L-glutamine (Gln) and γ-aminobutyric acid (GABA) (purity ≥ 99 %, Sigma-Aldrich, St. Louis, Missouri, USA). The analytical measurements of the derivatized FAA, derivatization was performed using AccQ-Tag™ precolumn derivatization method (Waters, Eschborn, Germany), were performed with ultra high performance liquid chromatography with electrospray ionization and Orbitrap mass spectrometry (UHPLC/ESI Orbtitrap-MS).