| Zugriffsnummer | 28533 |
| Dokumenttyp | Zeitschriftenartikel |
| Sprache | Englisch |
| Titel | Silicon isotope ratios affected by solium-induced broadband interference in high resolution MC-ICP-MS. |
| Autor(in); Institution |
Pramann, Axel; 3.1, Metrologie in der Chemie, PTB-Braunschweig
Rienitz, Olaf; 3.1, Metrologie in der Chemie, PTB-Braunschweig
Schiel, Detlef; 3.1, Metrologie in der Chemie, PTB-Braunschweig
|
| Quelle/Jahr | Analytical Chemistry: 84 (2012), 33, 10175 - 10179 |
| ISSN | 0003-2700 (PRINT) ; 1520-6882 (ONLINE) |
| DOI | |
| Verlag | Washington, DC: American Chemical Society |
| Zusammenfassung | The measurement of isotope ratios of silicon material highly enrichted in 28Si (“Si28”, x(28Si) ) 99.99 %) was influenced by a significant interference pattern (20 %) on the 30Si+ signal when using a standard cup configuration of C (29Si+) and H3 (30Si+) of a NeptuneTM MC-ICP-MS. This interference was observed in silicon solutions of aqueous NaOH with (w(NaOH) ) 0.001 g/g) and in highly concentrated aqueous NaOH blank solution (e. g. w(NaOH) = 0.25 g/g), but never in KOH solutions. By redirecting the ions, the interference was detected with all other Faraday cups except the center cup. The interferecne can be explained by ion scattering induced in the presence of large amounts of sodium. Due to a shielded location, these stray ions were not detected in the center cup. This effect explains an anomalous icrease of the abundance of the 30Si+ signal in 30Si/29Si isotope ratio measurements using aqueous NaOH blank solutions with w(NaOH) ≥ 0.001 g/g which is important when matching sample and blank concentrations. For silicon measurements it is recommended to use stron alkaline solutions that do not contain sodium. These findings are extremely important for the experimental determination of the Avogadro constand NA using the “silicon route”, but also in more general topics like isototope analysis in matrices with high concentrations of sodium (e. g. seawater). |
