Steady analyses of potassium stable isotopes using a Thermo Scientific Neoma MC-ICP-MS

Abstract

Potassium stable isotope compositions (41K/39K ratio) exhibit a wide range of natural variation (~ 3‰), which measurement has been recently achievable thanks to the development of various methods, including collision...

Atomic spectrometry update: review of advances in the analysis of clinical and biological materials, foods and beverages

“…Meanwhile, the performance of a new pseudo high sensitivity MC-ICP-MS instrument (Thermo Scientific Neoma), which incorporates 11 independent Faraday cups connected to 20 amplifier slots, for measuring K isotope ratios ( 41 K : 39 K) in clinical samples under hot plasma conditions was assessed. 88 A relative insensitivity to matrix effects was accomplished through the newly designed sample introduction system integrating an iCAP Qnova Series ICP-MS torch and injector assembly. Intermediate precision was reported as 0.07‰.…”

Significantly Enhanced Robustness of K Isotope Analysis by Collision Cell MC-ICP-MS and Its Application to the Returned Lunar Samples by China’s Chang’e-5 Project

“…Researchers continued to use the state-of-the-art mass spectrometry of their times to analyze K isotopes, and the precision of K isotope analysis was improved to ±1‰ in the 1970s by using thermo ionization mass spectrometry (e.g., refs and ) and to ±0.5‰ in the 1990s by using secondary ionization mass spectrometry (e.g., ref ), but the precision was still not sufficient to discern most natural K isotope variability from terrestrial samples. Since 2016, multicollector ICP mass spectrometry (MC-ICP-MS) has become the mainstream method to measure 41 K/ 39 K ratios with analytical precision pushed to a level of <0.1‰, which finally opened the door to the full application of stable K isotope ratios to study various natural processes, and an explosion in K isotope research is ongoing. ,− …”

“…Two approaches have been adopted to overcome this obstacle. One is to run MC-ICP-MS under high mass resolution mode, with cold plasma ,,,,,, or without cold plasma, ,, to physically resolve 40 Ar 1 H + from 41 K + in the mass spectrometer. The other approach is to remove 40 Ar 1 H + chemically by collision and reaction with gas molecules in the collision cell of MC-ICP-MS (e.g., refs , , , , , , and ).…”

Experimental investigation of improved tolerance for concentration mismatch in potassium isotope analysis on a hexapole collision cell MC-ICP-MS (Nu Sapphire)

“…6 Such argide interference can be reduced through cold plasma and/or dry plasma with high 8 to extra-high mass resolution. 9–11 This approach, however, is accompanied by a significant loss of the signal and thus requires high sample concentrations.…”