A new method for the determination of low-level actinium-227 in geological samples

  • Henrieta DulaiovaEmail author
  • Kenneth W. W. Sims
  • Matthew A. Charette
  • Julie Prytulak
  • Jerzy S. Blusztajn


We developed a new method for the determination of 227Ac in geological samples. The method uses extraction chromatographic techniques and alpha-spectrometry and is applicable for a range of natural matrices. Here we report on the procedure and results of the analysis of water (fresh and seawater) and rock samples. Water samples were acidified and rock samples underwent total dissolution via acid leaching. A DGA (N,N,N′,N′-tetra-n-octyldiglycolamide) extraction chromatographic column was used for the separation of actinium. The actinium fraction was prepared for alpha spectrometric measurement via cerium fluoride micro-precipitation. Recoveries of actinium in water samples were 80 ± 8 % (number of analyses n = 14) and in rock samples 70 ± 12 % (n = 30). The minimum detectable activities (MDA) were 0.017–0.5 Bq kg−1 for both matrices. Rock sample 227Ac activities ranged from 0.17 to 8.3 Bq kg−1 and water sample activities ranged from below MDA values to 14 Bq kg−1of 227Ac. From the analysis of several standard rock and water samples with the method we found very good agreement between our results and certified values.


Actinium-227 Extraction chromatography Water Rock Alpha-spectrometry 



We would like to acknowledge Phil Horwitz and William Burnett for their advice on the extraction chromatographic techniques. Ken Sims’ lab at the Woods Hole Oceanographic Institution performed the rock dissolution procedures and Ken Buesseler (WHOI) provided the counting equipment for the alpha-spec analysis. Jan Scholten from the IAEA provided the actinium standard and spiked seawater samples.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2012

Authors and Affiliations

  • Henrieta Dulaiova
    • 1
    Email author
  • Kenneth W. W. Sims
    • 2
  • Matthew A. Charette
    • 3
  • Julie Prytulak
    • 4
  • Jerzy S. Blusztajn
    • 5
  1. 1.Department of Geology and GeophysicsUniversity of HawaiiHonoluluUSA
  2. 2.Department of Geology and GeophysicsUniversity of WyomingLaramieUSA
  3. 3.Department of Marine Chemistry and GeochemistryWoods Hole Oceanographic InstitutionWoods HoleUSA
  4. 4.Department of Earth Science and EngineeringImperial CollegeLondonUK
  5. 5.Department of Geology and GeophysicsWoods Hole Oceanographic InstitutionWoods HoleUSA

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