Importance of Analyte-matrix Separation in U-Pb and Pb-Pb
Dating Systems
Jan DOBEŠ1
, Vladimír KISTAN1
, Markéta HOLÁ1
, Vojtěch WERTICH2
,
Viktor KANICKÝ1
1
Masaryk University, Department of Chemistry, Faculty of Science, Kotlářská 2, 611 37
Brno, Czech Republic
2
Masaryk University, Department of Geological Sciences, Faculty of Science, Kotlářská 2,
611 37 Brno, Czech Republic
Dating is nowadays widely used analytical approach combing geology and analytical
chemistry. It provides useful geochronological information in specific areas. Inductively
coupled plasma mass spectrometry (ICP-MS) is still one of the common methods used for
elemental and isotope ratios analysis [1]. The dating principle assumes that the age of a sample
can be calculated from the ratio of two or more isotopes present in the sample. To determine
the isotope ratios, sample preparation is crucial in order to eliminate interferences and improve
accuracy and precision [2].
Besides ore mining, manual separation, sample digestion and dissolution, the critical step in the
preparation procedure is analyte-matrix separation. Uranium and lead are usually separated
from sample matrix by the principles of ion exchange chromatography using previously
developed procedures [3, 4] or new approaches can be introduced. In this study, series of U and
Pb standard solutions were used to optimize the separation procedure using commercially
available resins. Different eluting agents were tested. After the method optimization, uraninite
samples were analysed. For both elemental and isotopic analysis, solution method ICP-MS was
used.
Key words: ICP-MS, uranium-lead dating system, ion exchange chromatography, dating
References:
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in Analytical Chemistry 27(5) (2008) 460-480.
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AMBERLITE IR-120 SEPARATION FROM MIXTURES, Analytica Chimica Acta 22(2)
(1960) 153-158.
[4] F.W.E. Strelow, APPLICATION OF ION EXCHANGE CHROMATOGRAPHY TO
ACCURATE DETERMINATION OF LEAD URANIUM AND THORIUM IN TANTALONIOBATES,
Analytical Chemistry 39(12) (1967) 1454-&.