Investigating the differences between MC-ICP-MS and MC-TIMS using conventional 87Sr/86Sr isotope ratios in limestone and slate reference materials
- The Federal Institute for Materials Research and Testing (BAM) organised an interlaboratory comparison (ILC) for the characterisation of 87Sr/86Sr isotope ratios in limestone (IAG/CGL ML-3) and Penrhyn slate (IAG OU-6) reference materials by applying the conventional method for 87Sr/86Sr isotope ratios. Samples were sent to thirteen analytical laboratories . Since both samples are powdered, rock materials, dissolution of the sample and Sr isolation via ion exchange chromatography were mandatory. This was done using acid, microwave/acid, bomb/acid digestion or borate fusion and subsequent isolation of Sr by means of commercially available ion exchange resins. In this study, we present and discuss the potential effects that differences between laboratories, and between two instrumental measurement techniques (i.e., MC-ICP-MS and MC-TIMS), may have upon the dispersion of measurement results of the 87Sr/86Sr isotope ratio in the two aforementioned reference materials. We used aThe Federal Institute for Materials Research and Testing (BAM) organised an interlaboratory comparison (ILC) for the characterisation of 87Sr/86Sr isotope ratios in limestone (IAG/CGL ML-3) and Penrhyn slate (IAG OU-6) reference materials by applying the conventional method for 87Sr/86Sr isotope ratios. Samples were sent to thirteen analytical laboratories . Since both samples are powdered, rock materials, dissolution of the sample and Sr isolation via ion exchange chromatography were mandatory. This was done using acid, microwave/acid, bomb/acid digestion or borate fusion and subsequent isolation of Sr by means of commercially available ion exchange resins. In this study, we present and discuss the potential effects that differences between laboratories, and between two instrumental measurement techniques (i.e., MC-ICP-MS and MC-TIMS), may have upon the dispersion of measurement results of the 87Sr/86Sr isotope ratio in the two aforementioned reference materials. We used a statistical mixed effects model to assess the potential effects of both the laboratory and the measurement technique. Consensus values for both materials and associated standard uncertainties {(IAG/CGL ML-3 (0.708245±0.000004) mol/mol; IAG OU-6 (0.729769±0.000008) mol/mol} were estimated by fitting a linear, Gaussian mixed effects model (Pinheiro and Bates 2000) using the R function “lmer” defined in package “lme4”. The statistical results showed that there is no significant effect attributable to differences between instrumental techniques when both materials are considered together, or separately. The p-value of the test of significance of the measurement technique effect is greater than 0.54. For both materials there were statistically significant effects attributable to differences between laboratories when the measurement results for both materials were considered together and separately. This effect is less than 0.00004 in absolute value. However, for neither material did consideration or disregard for such differences induce significant changes in the estimate of the consensus value for the 87Sr/86Sr isotope ratio. Therefore, the effects attributable to differences between instrumental techniques or between laboratories can safely be disregarded when computing the best estimate for the true value of 87Sr/86Sr isotope ratio in these materials, by the community of expert laboratories represented in this study.…
Autor*innen: | Anera KazlagicORCiD, M. Rosner, Jochen VoglORCiD |
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Koautor*innen: | A. Cipriani, D. A. Frick, J. Glodny, J. E. Hoffmann, J. M. Hora, J. Irrgeher, F. Lugli, T. Magna, T. C. Meisel, A. Meixner, A. Possolo, A. Pramann, M. Pribil, T. Prohaska, A. Retzmann, O. Rienitz, D. Rutherford, G. Paula-Santos, M. Tatzel, S. Widhalm, M. Willbold, T. Zuliani |
Dokumenttyp: | Posterpräsentation |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2022 |
Organisationseinheit der BAM: | 1 Analytische Chemie; Referenzmaterialien |
1 Analytische Chemie; Referenzmaterialien / 1.1 Anorganische Spurenanalytik | |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | Conventional isotope ratio; ILC; Isotope ratio; Isotope reference materials; Traceability; Uncertainty |
Themenfelder/Aktivitätsfelder der BAM: | Chemie und Prozesstechnik |
Veranstaltung: | GeoAnalysis 2022 |
Veranstaltungsort: | Freiberg, Germany |
Beginndatum der Veranstaltung: | 06.08.2022 |
Enddatum der Veranstaltung: | 12.08.2022 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 19.01.2023 |
Referierte Publikation: | Nein |