umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Mercury species transformations during sample pre-treatment of biological tissues studied by HPLC-ICP-MS
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
2002 (English)In: Journal of Analytical Atomic Spectrometry, ISSN 0267-9477, E-ISSN 1364-5544, Vol. 17, no 11, 1486-1491 p.Article in journal (Refereed) Published
Abstract [en]

A high-performance liquid chromatography (HPLC) system with a C18 column and an aqueous phase eluent (0.08% ammonium acetate and 0.02% L-cysteine) was directly connected to an inductively coupled plasma mass spectrometer (ICP-MS). HPLC-ICP-MS was used to study the abiotic formation of methylmercury, CH3Hg+, from inorganic mercury, Hg2+, as well as demethylation of CH3Hg+ to Hg2+ in biological tissues during treatment with tetramethylammonium hydroxide (TMAH) followed by pH adjustment with citric or acetic acid. Enriched isotope standards from CH3198Hg+ and 201Hg2+ were added to the samples to monitor species transformation and to apply species-specific isotope dilution (SSID) calibration. Depending on the type of sample matrix, up to 11.5% of added Hg2+ was methylated and up to 6.26% CH3Hg+ was demethylated to Hg2+. Methylation of Hg2+ probably takes place mainly during and after pH adjustment and it decreases after prolonged TMAH treatment. To minimize abiotic methylation, it is therefore recommended to proceed with pH adjustment after samples have been treated with TMAH for 24 h. There is no significant difference in the degree of methylation using citric or acetic acid.

Place, publisher, year, edition, pages
RSC Publishing, 2002. Vol. 17, no 11, 1486-1491 p.
National Category
Chemical Sciences
Identifiers
URN: urn:nbn:se:umu:diva-2294DOI: 10.1039/B205246FOAI: oai:DiVA.org:umu-2294DiVA: diva2:140229
Available from: 2003-09-25 Created: 2003-09-25 Last updated: 2017-12-14Bibliographically approved
In thesis
1. On the reliability of methods for the speciation of mercury based on chromatographic separation coupled to atomic spectrometric detection
Open this publication in new window or tab >>On the reliability of methods for the speciation of mercury based on chromatographic separation coupled to atomic spectrometric detection
2003 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis deals with the reliability of methods for the speciation of mercury in environmental and biological samples. Problems with speciation methods that couple chromatography to atomic spectrometric detection and how to overcome the problems are discussed. Analytical techniques primarily studied and evaluated are high performance liquid chromatography-cold vapour-atomic absorption spectrometry (HPLC-CV-AAS), HPLC-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS), capillary electrophoresis-ICP-MS (CE-ICP-MS) and gas chromatography-ICP-MS (GC-ICP-MS). Applying a multi-capillary approach increased the analyte amount injected into a CE-ICP-MS system and improved the overall sensitivity. A microconcentric nebulizer with a cyclone spray chamber was shown to improve the detection limits for mercury species 3-13 times in HPLC-ICP-MS and 11-19 times in CE-ICP-MS compared to a cross-flow nebulizer with a Scott spray chamber. To decrease the interference of water vapour in HPLC-CV-AAS a Nafion dryer tube was inserted between the CV-generation and the detector. Methyl mercury was however lost in the Nafion unless it was reduced to elemental mercury prior transport through the dryer tube.

During sample pre-treatment, incomplete extraction, losses and transformation (alkylation, dealkylation, oxidation and reduction) of mercury species can lead to significant errors (underestimation and overestimation) in the determination of the concentrations. Methods to detect and determine the degree of transformation as well as correct for errors caused by transformation are presented in the thesis. The preferable method use species-specific enriched stable isotope standards in combination with MS detection and a matrix based calculation scheme. This approach is very powerful as both the concentrations of the species as well as the degrees of transformation can be determined within each individual sample.

Publisher
35 p.
Keyword
Analytical chemistry, Mercury, speciation, hyphenated techniques, HPLC, CE, GC, CV-AAS, ICP-MS, species-specific enriched stable isotope, Analytisk kemi
National Category
Analytical Chemistry
Research subject
Analytical Chemistry
Identifiers
urn:nbn:se:umu:diva-111 (URN)91-7305-429-1 (ISBN)
Public defence
2003-05-23, Umeå, 13:00 (English)
Available from: 2003-09-25 Created: 2003-09-25 Last updated: 2009-05-25Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Qvarnström, JohannaFrech, W.
By organisation
Department of Chemistry
In the same journal
Journal of Analytical Atomic Spectrometry
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 106 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf