Determination of picogram amounts of uranium in micrometre-sized particles by isotope dilution mass spectrometry

In order to improve the analytical methods used in the field of particle analysis in nuclear safeguards, monodispersed micrometre-sized particles with certified uranium isotopic composition and uranium amount per particle are highly useful. In this study, picogram amounts of uranium in particle form were quantified in a candidate particle reference material for certification. The uranium amount per particle was determined using optical microscopy combined with Isotope Dilution Thermal Ionisation Mass Spectrometry (ID-TIMS). The uranium amount was verified using Isotope Dilution Mufti Collection Inductively Coupled Plasma Mass Spectrometry (ID-MC-ICPMS). The uranium amount per particle agreed well between the two techniques within the associated uncertainties. Both techniques are suitable for quantification of picogram amounts of uranium in particulate reference materials. The uranium particle material in this study was Eater used in a proficiency test (NUSIMEP-9) and eventually certified for the uranium isotopic composition of particles and the uranium amount per particle.

Automated summary

In this study, picogram amounts of uranium in particle form were quantified using optical microscopy combined with Isotope Dilution Thermal Ionisation Mass Spectrometry (ID-TIMS). The uranium amount was verified using Isotope Dilution Mufti Collection Inductively Coupled Plasma Mass Spectrometry (ID-MC-ICPMS), and both techniques showed good agreement within uncertainties. The uranium particle material in this study was eventually certified for the uranium isotopic composition of particles and the uranium amount per particle, proving the suitability of the techniques for quantifying picogram amounts of uranium in particulate reference materials.