title: Inter-laboratory calibration of new silver orthophosphate comparison materials for the stable oxygen isotope analysis of phosphates.
abstract: Stable oxygen isotope compositions (δ(18)O values) of two commercial and one synthesized silver orthophosphate reagents have been determined on the VSMOW scale. The analyses were carried out in three different laboratories: lab (1) applying off-line oxygen extraction in the form of CO(2) which was analyzed on a dual inlet and triple collector isotope ratio mass spectrometer, while labs (2) and (3) employed an isotope ratio mass spectrometer coupled to a high-temperature conversion/elemental analyzer (TC/EA) where Ag(3)PO(4) samples were analyzed as CO in continuous flow mode. The δ(18)O values for the proposed new comparison materials were linked to the generally accepted δ(18)O values for Vennemann's TU-1 and TU-2 standards as well as for Ag(3)PO(4) extracted from NBS120c. The weighted average δ(18)O(VSMOW) values for the new comparison materials UMCS-1, UMCS-2 and AGPO-SCRI were determined to be + 32.60 (± 0.12), + 19.40 (± 0.12) and + 14.58 (± 0.13)‰, respectively.
authors.affiliation: Mass Spectrometry Laboratory, Institute of Physics, Marie Curie-Sklodowska University, Lublin, Poland. stanislaw.halas@umcs.lublin.pl
authors.forename: Stanislaw
authors.initials: S
authors.lastname: Halas
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Skrzypek
authors.forename: Wolfram
authors.initials: W
authors.lastname: Meier-Augenstein
authors.forename: Andrzej
authors.initials: A
authors.lastname: Pelc
authors.forename: Helen F
authors.initials: HF
authors.lastname: Kemp
mesh_terms: D002138:Calibration; D007553:Isotope Labeling / Q000379:methods / Q000592:standards*; D019995:Laboratory Chemicals / Q000737:chemistry; D013058:Mass Spectrometry / Q000592:standards; D010103:Oxygen Isotopes / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D012015:Reference Standards; D018030:Silver Compounds / Q000737:chemistry*
chemical_list: D019995:Laboratory Chemicals; D010103:Oxygen Isotopes; D010710:Phosphates; D018030:Silver Compounds; C039072:silver phosphate