Hi Bill,
check the following references for d18O of cellulose:
Werner, Kornexl, Rossmann and Schmidt, Anal Chim Acta 319, 159 (1996)
Koziet, J Mass Spectrom 32, 103 (1997)
Farquhar, Henry and Styles, Rapid Commun Mass Spectrom 11, 1554 (1997)
Breas, Guillou, Reniero, Sada and Angerosa, Rapid Commun Mass Spectrom 12,
188 (1998)
Saurer, Robertson, Siegwolf und Leuenberger, Anal Chem (1998)
Werner et al use a conventional EA supplying a temperature of 1100°C, which
is enough if you really want to do only cellulose and other carbohydrates
(no inorganics). Saurer et al. uses this method for routine cellulose
analysis and discusses the system in detail.
Koziet uses an EA supplying a higher oxidation furnace temperature
(1350)°C). The use of a tube-in-tube construction of the pyrolysis tube and
the high temperature are features that are necessary if you need a more
universally applicable system (all kinds of organics, plus inorganics such
as nitrate, sulphate, phosphate -- and water). I think the Finnigan
EA-Pyrolysis-IRMS system works that way, and we use a similar method here
in Leipzig (at 1400°C, to be published - I hope soon...).
Micromass uses the Farquhar method (they work at 1100°C); nitrogen in the
sample is no problem with neither system, presuming you use a suitable
separation column (e.g. mol sieve 5A) - even if the title of the Farquhar
paper gives this impression.
Werner, Farquhar and Breas all use a quite similar set-up with no
high-temperature furnace necessary. This will do for you, if cellulose is
what you want to analyze. If you consider cellulose a first step, and you
think inorganics might be the second one, you will need the
high-temperature furnace.
If you have any other questions, you can also contact me directly
Good Luck
Barbara
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Dr. Barbara E. Kornexl
UFZ - Umweltforschungzentrum Leipzig-Halle GmbH
Sektion Analytik
Permoserstr. 15
D-04318 Leipzig
Tel.: ++49/341/235- 2252
Fax: 2625
E-Mail: [log in to unmask]
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