Published:Journal of Chromatographic Science,
ISSN 0021-9665Volume
37, Number 7, July 1999, pp.245-250
Modelling of the Effect of
Chromatographic Resolution on the Determination of the UK37' IndexPau Comes and Antoni Rosell-Melé
The UK37' index is based on the measurement of the relative abundance of C37
alkenones in marine samples and is used to estimate absolute palaeo-sea surface
temperatures. The reliability of the data (and the value of their interpretation)
depends on the minimization of those factors that give rise to errors in the
measurement of UK37'. The index is calculated using gas chromatography, and
here, the effect of chromatographic resolution on UK37' is evaluated through
the modelling of chromatograms with Gaussian or exponentially modified Gaussian
peaks. It is shown that chromatographic resolution of the alkenones is indeed
linked to the accuracy of UK37', although the magnitude of the error depends
on the actual values of UK37', the degree of peak tailing, and the relative
abundance of coelutants. However, it is not necessary to achieve baseline separation
between the alkenones to obtain UK37' values with errors that are climatically
nonsignificant. Further work should demonstrate if these results can be reproduced
experimentally, but in principle, the use of partially unresolved chromatograms
with or without peak tailing does not appear to be a major source of error during
UK37' analysis.
Reproduction
of editorial content of this journal is prohibited without publishers
permission.
This
article is available in its entirety by fax for $4.00 per
page.
Visa or MasterCard accepted.
To
order electronicallyclick here or call: 847-647-2900 ext. 1323 or fax request to: 847-647-1155.
Please
indicate JCS volume and issue along with
page numbers.