Abstract
The use of isotopic carbon dioxide lasers for determination of carbon (and oxygen) isotope ratios was first demonstrated in 1994. Since then a commercial device called LARA™, has been manufactured and used for Helicobacter pylori breath tests using 13C-labelled urea. The major advantages of the optogalvanic effect compared with other infrared absorption isotope ratio measurement techniques are its lack of optical background and its high sensitivity resulting from a signal gain proportional to laser power. Continuous normalisation using two cells, a standard and sample, lead to high accuracy as well as precision. Recent advances in continuous flow measurement of 13C/12C ratios of CO2 in air and extensions of the technique to 14C, which can be analysed as a stable isotope, are described.
Original language | English (US) |
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Pages (from-to) | 363-371 |
Number of pages | 9 |
Journal | Isotopes in Environmental and Health Studies |
Volume | 41 |
Issue number | 4 |
DOIs | |
State | Published - Dec 2005 |
All Science Journal Classification (ASJC) codes
- Environmental Chemistry
- Environmental Science(all)
- Inorganic Chemistry
Keywords
- Carbon dioxide
- Carbon-13
- Carbon-14
- IR spectrometry
- Isotope analysis
- Isotopic carbon dioxide lasers
- Optogalvanic detection