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Gravimetric deposition of microliter drops with radiometric confirmation



Denis E. Bergeron, Richard Essex, Svetlana Nour, Gordon A. Shaw, R. Michael Verkouteren, Ryan P. Fitzgerald


A manual gravimetric dispensing technique is demonstrated using a micropipettor modified for use with removeable microcapillaries. Liquid scintillation sources were prepared from a well-characterized 241Am reference solution, providing a radiometric check of dispensed masses. Further experiments confirmed controlled dispensing of drops onto gold foils with losses ≤ 0.34(4) % of the total drop activity. A detailed measurement equation for the weighing technique, including the corrections for evaporation, is presented with a full accounting of associated uncertainties.
Applied Radiation and Isotopes


Milligram mass metrology, quantitative drop deposition, decay energy spectrometry source, Am-241


Bergeron, D. , Essex, R. , Nour, S. , Shaw, G. , Verkouteren, R. and Fitzgerald, R. (2023), Gravimetric deposition of microliter drops with radiometric confirmation, Applied Radiation and Isotopes, [online],, (Accessed July 15, 2024)


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Created September 9, 2023, Updated September 15, 2023