Performance of Neoma MS/MS MC-ICP-MS for analysis of radiogenic isotopes

Importance of the topic

Radiogenic isotopes such as hafnium, lead, neodymium and strontium serve as indispensable tools in Earth and planetary sciences. Their decay-derived signatures allow precise dating of geological events, tracing crustal and mantle differentiation, and understanding the origin of surface and subsurface materials including Earth’s water.

Study objectives and overview

This application note evaluates the performance of the Thermo Scientific™ Neoma™ MS/MS MC-ICP-MS for measuring non-traditional radiogenic isotope systems. Nine instruments in the Bremen facility were tested to assess sensitivity, mass bias behavior, accuracy and reproducibility for standard solutions of Hf, Pb, Nd and Sr.

Methodology

• Full ion transmission mode with the pre-cell mass filter slit set to 100% and no collision/reaction cell gas.
• Wet plasma operation, 10 minutes per sample, without standard-sample bracketing.
• Applied exponential mass bias corrections and interference corrections: Yb and W on Hf; Hg on Pb; Ce and Sm on Nd; Kr and Rb on Sr.

Used instrumentation

• Thermo Scientific Neoma MS/MS MC-ICP-MS with SIS spray chamber.
• ESI 100 µL/min microFAST MC syringe injection autosampler.
• Nickel X skimmer cone and Jet sampler cone in low-resolution mode.

Results and discussion

• Sensitivities exceeded specifications in wet plasma: up to 110 V/ppm for Hf, 90 V/ppm for Pb and Nd, and 64 V/ppm for Sr.
• Mass bias followed an exponential law across all nine instruments and isotopic systems, confirming validity of exponential corrections.
• Cross-instrument reproducibility showed external precision mirroring internal precision, with relative standard deviations of 20–60 ppm for most isotope ratios; low-abundance isotopes (¹⁰⁴Pb, ⁸⁴Sr) exhibited higher variability.
• Measured precision closely matched predictions based on counting statistics and Johnson-Nyquist noise, indicating these as the dominant uncertainty sources.

Benefits and practical applications

The Neoma MS/MS MC-ICP-MS enables accurate, high-precision isotope ratio measurements without bracketing, ensuring consistent results in multi-user laboratories. Its performance supports diverse applications including geochronology, planetary differentiation studies and environmental tracing.

Future trends and opportunities

Advances are expected in dry plasma sensitivity enhancements, optimized collision/reaction cell chemistries, integration with laser ablation sources for spatially resolved analyses, and expansion to additional non-traditional radiogenic isotope systems.

Conclusion

The Neoma MS/MS MC-ICP-MS demonstrates robust exponential mass bias behavior, accurate unbracketed isotope ratios and consistent precision across instruments. Analytical uncertainty is dominated by counting statistics and electronic noise, underlining the system’s suitability for high-precision radiogenic isotope investigations.

No formal literature list was provided in the source.