On-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques
The high temperature conversion (HTC) technique using an elemental analyzer with a glassy carbon tube and filling (temperature conversion/elemental analysis, TC/EA) is a widely used method for hydrogen isotopic analysis of water and many solid and liquid organic samples with analysis by isotope-rati...
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American Chemical Society (ACS), Washington, DC
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ftufz:oai:ufz.de:16170 2023-12-10T09:43:02+01:00 On-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques Gehre, Matthias Renpenning, Julian Gilevska, Tetyana Qi, H. Coplen, T.B. Meijer, H.A.J. Brand, W.A. Schimmelmann, A. 2015-04-15 application/pdf https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=16170 https://doi.org/10.1021/acs.analchem.5b00085 en eng American Chemical Society (ACS), Washington, DC Analytical Chemistry 87 (10);; 5198 - 5205 https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=16170 https://dx.doi.org/10.1021/acs.analchem.5b00085 info:eu-repo/semantics/closedAccess ISSN: 0003-2700 info:eu-repo/semantics/article https://purl.org/dc/dcmitype/Text 2015 ftufz https://doi.org/10.1021/acs.analchem.5b00085 2023-11-12T23:33:18Z The high temperature conversion (HTC) technique using an elemental analyzer with a glassy carbon tube and filling (temperature conversion/elemental analysis, TC/EA) is a widely used method for hydrogen isotopic analysis of water and many solid and liquid organic samples with analysis by isotope-ratio mass spectrometry (IRMS). However, the TC/EA IRMS method may produce inaccurate δ2H results, with values deviating by more than 20 mUr (milliurey = 0.001 = 1‰) from the true value for some materials. We show that a single-oven, chromium-filled elemental analyzer coupled to an IRMS substantially improves the measurement quality and reliability for hydrogen isotopic compositions of organic substances (Cr-EA method). Hot chromium maximizes the yield of molecular hydrogen in a helium carrier gas by irreversibly and quantitatively scavenging all reactive elements except hydrogen. In contrast, under TC/EA conditions, heteroelements like nitrogen or chlorine (and other halogens) can form hydrogen cyanide (HCN) or hydrogen chloride (HCl) and this can cause isotopic fractionation. The Cr-EA technique thus expands the analytical possibilities for on-line hydrogen-isotope measurements of organic samples significantly. This method yielded reproducibility values (1-sigma) for δ2H measurements on water and caffeine samples of better than 1.0 and 0.5 mUr, respectively. To overcome handling problems with water as the principal calibration anchor for hydrogen isotopic measurements, we have employed an effective and simple strategy using reference waters or other liquids sealed in silver-tube segments. These crimped silver tubes can be employed in both the Cr-EA and TC/EA techniques. They simplify considerably the normalization of hydrogen-isotope measurement data to the VSMOW-SLAP (Vienna Standard Mean Ocean Water-Standard Light Antarctic Precipitation) scale, and their use improves accuracy of the data by eliminating evaporative loss and associated isotopic fractionation while handling water as a bulk sample. The calibration of ... Article in Journal/Newspaper Antarc* Antarctic UFZ - Publication Index (Helmholtz-Centre for Environmental Research) Antarctic Analytical Chemistry 87 10 5198 5205 |
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English |
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The high temperature conversion (HTC) technique using an elemental analyzer with a glassy carbon tube and filling (temperature conversion/elemental analysis, TC/EA) is a widely used method for hydrogen isotopic analysis of water and many solid and liquid organic samples with analysis by isotope-ratio mass spectrometry (IRMS). However, the TC/EA IRMS method may produce inaccurate δ2H results, with values deviating by more than 20 mUr (milliurey = 0.001 = 1‰) from the true value for some materials. We show that a single-oven, chromium-filled elemental analyzer coupled to an IRMS substantially improves the measurement quality and reliability for hydrogen isotopic compositions of organic substances (Cr-EA method). Hot chromium maximizes the yield of molecular hydrogen in a helium carrier gas by irreversibly and quantitatively scavenging all reactive elements except hydrogen. In contrast, under TC/EA conditions, heteroelements like nitrogen or chlorine (and other halogens) can form hydrogen cyanide (HCN) or hydrogen chloride (HCl) and this can cause isotopic fractionation. The Cr-EA technique thus expands the analytical possibilities for on-line hydrogen-isotope measurements of organic samples significantly. This method yielded reproducibility values (1-sigma) for δ2H measurements on water and caffeine samples of better than 1.0 and 0.5 mUr, respectively. To overcome handling problems with water as the principal calibration anchor for hydrogen isotopic measurements, we have employed an effective and simple strategy using reference waters or other liquids sealed in silver-tube segments. These crimped silver tubes can be employed in both the Cr-EA and TC/EA techniques. They simplify considerably the normalization of hydrogen-isotope measurement data to the VSMOW-SLAP (Vienna Standard Mean Ocean Water-Standard Light Antarctic Precipitation) scale, and their use improves accuracy of the data by eliminating evaporative loss and associated isotopic fractionation while handling water as a bulk sample. The calibration of ... |
format |
Article in Journal/Newspaper |
author |
Gehre, Matthias Renpenning, Julian Gilevska, Tetyana Qi, H. Coplen, T.B. Meijer, H.A.J. Brand, W.A. Schimmelmann, A. |
spellingShingle |
Gehre, Matthias Renpenning, Julian Gilevska, Tetyana Qi, H. Coplen, T.B. Meijer, H.A.J. Brand, W.A. Schimmelmann, A. On-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques |
author_facet |
Gehre, Matthias Renpenning, Julian Gilevska, Tetyana Qi, H. Coplen, T.B. Meijer, H.A.J. Brand, W.A. Schimmelmann, A. |
author_sort |
Gehre, Matthias |
title |
On-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques |
title_short |
On-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques |
title_full |
On-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques |
title_fullStr |
On-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques |
title_full_unstemmed |
On-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques |
title_sort |
on-line hydrogen-isotope measurements of organic samples using elemental chromium: an extension for high temperature elemental-analyzer techniques |
publisher |
American Chemical Society (ACS), Washington, DC |
publishDate |
2015 |
url |
https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=16170 https://doi.org/10.1021/acs.analchem.5b00085 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
ISSN: 0003-2700 |
op_relation |
https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=16170 https://dx.doi.org/10.1021/acs.analchem.5b00085 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1021/acs.analchem.5b00085 |
container_title |
Analytical Chemistry |
container_volume |
87 |
container_issue |
10 |
container_start_page |
5198 |
op_container_end_page |
5205 |
_version_ |
1784886151142703104 |