Quantum mechanics

Statistics

Chromatography

Nuclear physics

Plasma

Calibration

Computer science

Inductively coupled plasma

Resolution (logic)

Geology

Oceanography

Physics

Organic chemistry

Mathematics

Isotope analysis

Inductively coupled plasma mass spectrometry

Artificial intelligence

Analytical Chemistry (journal)

Mass spectrometry

Chemistry

Nickel

Isotope

International Journal of Mass Spectrometry

Herein, we describe the use of a Nu Plasma 1700 multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) in true high-resolution mode to determine Fe isotopic ratios at the center of Fe peaks instead of their shoulders. A standard-sample bracketing (SSB) technique and a Ni doping method were used for instrumental mass bias calibration. The effects of Fe/Ni ratio and plasma mode were investigated in order to establish a high-precision Fe isotope analysis method. The results showed that the Ni-doping method provided more precision isotopic ratios than that of the SSB technique. Moreover, this work also presents Fe isotopic compositions of some geological reference materials (BCR-2, BHVO-2, AGV-2, GSR-1, GSR-2, GSR-3, GSP-2, and DSN-1), which were highly accurate with respect to the international Fe isotope standard IRMM-014. The iron isotopic compositions of most geological reference materials measured in this study agreed with the previously published data within quoted analytical uncertainties. Long-term reproducibility analyses of all samples indicate that the obtained isotopic ratios are highly reproducible, with precisions of better than ±0.03‰ for δ56Fe (2 sd) and ±0.06‰ (2 sd) for δ57Fe. Our results demonstrated the usefulness of internal element doping for improving the stability and precision of isotope analysis by MC-ICP-MS.

Improved nickel-corrected isotopic analysis of iron using high-resolution multi-collector inductively coupled plasma mass spectrometry