Capabilities of Laser Ablation–ICP-TOFMS Coupling for Isotopic Analysis of Individual Uranium Micrometric Particles
Anne-Laure Ronzani and co-authors describe the use of laser ablation sampling in combination with the icpTOF for the analysis of small (several µm) uranium particles of varying isotopic composition. Simultaneous acquisition of all masses uniquely enables TOF mass spectrometry to measure isotopic ratios even in the short transient signals obtained from each particle and laser shot.
Careful tuning is required to keep the signal within the linear dynamic range of the detector. Under these conditions, 235U/238U ratios could be measured approaching, and in some cases exceeding, the precision of previous measurements obtained on multi-collector (MC) ICP-MS. Minor isotope ratios (234U/238U and 236U/238U) could be successfully measured, albeit with limited precision due to very low signals.
The different populations of particles could be clearly distinguished in the data, demonstrating the potential for this method in environmental sampling for nuclear safety applications. More generally, this shows the potential for measuring highly precise isotopic measurements by LA-ICP-TOF-MS on the icpTOF.