Assessment of the precision and accuracy of thorium (²³²Th) and uranium (²³⁸U) measured by quadrupole based inductively coupled plasma-mass spectrometry using liquid nebulization, nanosecond and femtosecond laser ablation

Abstract

The precision and accuracy of the 238 U/ 232 Th ratio were evaluated from liquid nebulization and direct solid sampling repetitive pulsed laser ablation. Nanosecond and femtosecond pulsed lasers at 266 nm wavelength were utilized for the ablation studies. The ICP-MS and sampling parameters were optimized for each procedure; flow rates, gases, laser energy and other parameters were optimized for the particular sampling approach and therefore will not be the same. The work is not a comparison per se but represents performance metrics for three optimized sampling modalities. As expected, nanosecond pulsed ablation provided the greatest inaccuracy (430%) from the nominal 238 U/ 232 Th bulk ratio. This deviation from bulk ratio is attributed to incomplete vaporization of large particle agglomerates produced by nanosecond laser ablation. Femtosecond pulsed ablation provided inaccuracy (B1-3%) approaching that of liquid nebulization (B1%). In terms of temporal relative standard deviation (TRSD) and relative standard deviation (RSD), liquid nebulization provided the best precision for the 238 U/ 232 Th ratio (TRSD B3-5%, RSD B0.2-0.6%), femtosecond laser ablation (TRSD B5-12%, RSD B1%) and nanosecond laser ablation (TRSD B25-48%, RSD B9-12%). Laser ablation requires less sample to achieve these performance metrics, in some cases less than a factor of 100-times depending on the entrainment and transport efficiency.

Application of femtosecond laser ablation inductively coupled plasma mass spectrometry for quantitative analysis of thin Cu(In,Ga)Se2 solar cell films

“…LA-ICP-MS is a powerful method for elemental analysis with advantages of realtime analysis [15,16], minimal sample consumption, no sample preparation [17], little waste, and minimal exposure to toxic samples [18]. Accordingly, LA-ICP-MS has been employed in various areas of application such as geochemistry [19], forensic science [20], environmental science [21], semiconductors [22], biomedicine [23], nuclear non-proliferation detection [24], and so forth.…”

“…Accordingly, LA-ICP-MS has been employed in various areas of application such as geochemistry [19], forensic science [20], environmental science [21], semiconductors [22], biomedicine [23], nuclear non-proliferation detection [24], and so forth. The coupling of femtosecond (fs) laser to ICP-MS (fs-LA-ICP-MS) has been demonstrated as one of the most accurate analytical methods due to the capability of near stoichiometric ablation and the generation of mono-disperse nanometer sized particles that can be easily digested in the ICP [18,25,26]. The analytical performance of LA-ICP-MS was significantly enhanced with a fs-laser by reducing errors related to particle size distribution and matrix dependence [27,28].…”

Laser Ablation Molecular Isotopic Spectrometry

“…High sensitivity and resolving power are characteristic of these mass spectrometric techniques but they generally tend to be laboratory-based and require complex sample preparation procedures. Laser ablation coupled with ICP-MS [9,10,[12][13][14] or laser desorption in MALDI-MS eliminates the need for laborious sample preparation.…”

Laser bidezko ablazioaren egungo egoera eta aplikazioak

“…Gainera, laser-materia elkarrekintza bortitzak tamaina handiko partikulak erauzten ditu, eta horrek aerosolaren garraioan eta atomizazio/ionizazio/detekzio prozesuetan eragina du. Femtosegundo laserrak, alabaina, efektu termiko mugatuak ditu, eta horrek ia kalterik ez egotea eta neurketaren doitasuna hobea izatea eragiten du [37][38][39].…”