Imperial College London
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DrKatharinaKreissig

Faculty of Engineering, Department of Earth Science & Engineering

Laboratory Manager
 
 
 
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Contact

 

+44 (0)20 7594 6517k.kreissig Website

 
 
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Location

 

2.47Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Griffiths:2020:10.1021/acs.analchem.0c01780,
author = {Griffiths, A and Packman, H and Leung, YL and Coles, BJ and Kreissig, K and Little, SH and van, de Flierdt T and Rehkämper, M},
doi = {10.1021/acs.analchem.0c01780},
journal = {Analytical Chemistry},
pages = {11232--11241},
title = {Evaluation of optimized procedures for high-precision Pb isotope analyses of seawater by MC-ICP-MS},
url = {http://dx.doi.org/10.1021/acs.analchem.0c01780},
volume = {92},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The application of Pb isotopes to marine geochemistry is currently hindered by challenges associated with the analysis of Pb isotopes in seawater. The current study evaluates the performance of MC-ICP-MS measurements of seawater Pb isotope compositions following Pb separation by either solid-phase extraction with Nobias Chelate PA-1 resin or co-precipitation with Mg(OH)2, and using either a Pb double-spike or external normalization to Tl for mass bias correction. The four analytical combinations achieve results of similar quality when measuring 1–7 ng of seawater Pb, with reproducibilities (2SD) of 100–1200 ppm for 206Pb/207Pb, 208Pb/207Pb and 300–1700 ppm for ratios involving the minor 204Pb isotope. All four procedures enable significantly improved sample throughout compared to an established TIMS double-spike method and produce unbiased seawater Pb isotope compositions with similar or improved precision. Nobias extraction is preferable to co-precipitation due to its greater analytical throughput and suitability for analyses of large seawater samples with high Si(OH)4 contents. The most accurate Pb isotope data are produced following Nobias extraction and double-spike correction as such analyses are least susceptible to matrix effects. However, Nobias extraction with Tl-normalization constitutes an attractive alternative as, unlike the double-spike procedure, only a single mass spectrometric measurement is required, which improves analytical throughput and optimizes Pb consumption for analysis. Despite the advantages of solid-phase extraction, co-precipitation represents a useful Pb separation technique for samples with low to moderate Si contents as it is inexpensive, simple to implement and the data are only marginally less accurate, especially when combined with a Pb double-spike for mass bias correction.
AU  - Griffiths,A
AU  - Packman,H
AU  - Leung,YL
AU  - Coles,BJ
AU  - Kreissig,K
AU  - Little,SH
AU  - van,de Flierdt T
AU  - Rehkämper,M
DO  - 10.1021/acs.analchem.0c01780
EP  - 11241
PY  - 2020///
SN  - 0003-2700
SP  - 11232
TI  - Evaluation of optimized procedures for high-precision Pb isotope analyses of seawater by MC-ICP-MS
T2  - Analytical Chemistry
UR  - http://dx.doi.org/10.1021/acs.analchem.0c01780
UR  - https://pubs.acs.org/doi/10.1021/acs.analchem.0c01780
UR  - http://hdl.handle.net/10044/1/80729
VL  - 92
ER  -
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