title: Comprehensive analysis of lipophilic arsenic species in a brown alga (Saccharina latissima).
abstract: Approaches for the unambiguous identification of lipophilic arsenic species in Saccharina latissima (sugar kelp) have been studied. Parallel use of high resolution ICPMS and electrospray ionization (ESI)-MS after separation revealed that Saccharina latissima contained three distinct classes of lipophilic As-species, a family of arsenic containing phospholipids (AsPL), all including As in the form of As-sugar-PO4, As-containing hydrocarbons (AsHC), and As-containing polyunsaturated fatty acids (AsFA). For detailed identification, the use of phospholipases, in particular phospholipase A2, was essential to define the fatty acid composition (determination of regioisomers) of the lipids without purification of the sample, while fragmentation of the molecules by MS(2) measurements alone did not supply this information. Some of the identified AsPL contained unsaturated fatty acids (C16:1, C18:1 to C18:3), but saturated fatty acids dominated the AsPL. The fatty acid bound to the position 2″ was predominantly C16:0. Complete lipid hydrolysis showed that this alga did not contain arsenic containing fatty acids (AsFA) bound to complex lipids. Our investigations indicate that in addition to RP-HPLC-ICPMS/ESI-MS a range of different derivatization methods should be used for the comprehensive identification of unknown lipid-soluble arsenic compounds.
authors: TESLA (Trace Element Speciation Laboratory), Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE, Scotland, United Kingdom.
authors: Andrea
authors: A
authors: Raab
authors: Chris
authors: C
authors: Newcombe
authors: Dominik
authors: D
authors: Pitton
authors: Rainer
authors: R
authors: Ebel
authors: Jörg
authors: J
authors: Feldmann
mesh_terms: D001152:Arsenicals / Q000032:analysis* / Q000737:chemistry* / Q000378:metabolism; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D005227:Fatty Acids / Q000032:analysis; D006838:Hydrocarbons / Q000032:analysis; D057927:Hydrophobic and Hydrophilic Interactions; D000459:Phaeophyceae / Q000737:chemistry* / Q000378:metabolism; D010743:Phospholipids / Q000032:analysis; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D001152:Arsenicals; D005227:Fatty Acids; D006838:Hydrocarbons; D010743:Phospholipids