title: Improved chromatographic separation of thio-arsenic compounds by reversed-phase high performance liquid chromatography-inductively coupled plasma mass spectrometry.
abstract: A new group of arsenic species, thio-arsenicals, have recently been reported in several natural samples such as molluscs, algae, and urine. These compounds are the sulfur analogues of oxo-arsenicals, a large group of naturally-occurring compounds, whereby the arsinoyl (As=O) group is substituted by an arsinothioyl group (As=S). The most common separation technique for oxo-arsenicals is anion-exchange HPLC with polymer-based columns, but under these conditions the thio-arsenicals show strong retention, resulting in unacceptably long analysis times and broad peaks. We report the development of a reversed-phase HPLC method, with ICPMS detection, which allows separation of the known thio-arsenicals within 15 min with significantly improved peak shapes. The detection limit is about 0.6 microg As/L based on 10 microL injection volume. Further, we have applied the method to the identification and quantification of thio-arsenic species in two standard reference materials, BCR 710 oyster tissue and NIES 18 human urine.
authors.affiliation: Karl-Franzens-University Graz, Institute of Chemistry-Analytical Chemistry, Universitaetsplatz 1, 8010 Graz, Austria.
authors.forename: Reingard
authors.initials: R
authors.lastname: Raml
authors.forename: Walter
authors.initials: W
authors.lastname: Goessler
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Francesconi
mesh_terms: D000818:Animals; D001152:Arsenicals / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification*; D002021:Buffers; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry / Q000379:methods*; D000432:Methanol / Q000737:chemistry; D010125:Ostreidae / Q000737:chemistry / Q000166:cytology; D012015:Reference Standards; D013438:Sulfhydryl Compounds / Q000032:analysis / Q000652:urine
chemical_list: D001152:Arsenicals; D002021:Buffers; D013438:Sulfhydryl Compounds; D000432:Methanol