Re: stable isotopic measurement of DOC
Amzad,

As Bill pointed out, a TIC/TOC analyzer is a good way to go, but if you don't have access to a TIC/TOC, you might want to look at the Gandhi et al. (2004) paper as an alternative technique.

Gandhi H., Wiegner T.N., Ostrom P.H., Kaplan L.A. and Ostrom N.E. (2004)
Isotopic (13C) analysis of dissolved organic carbon in stream water using an elemental analyzer coupled to a stable isotope ratio mass spectrometer.
Rapid Communications in Mass Spectrometry, 18: 903-906

Good luck!

Cheers,
Simon



Amzad
We use a TIC/TOC analyzer system interfaced to a continuous flow IRMS for
13C analysis of DIC and DOC. In this system, phosphoric acid drives DIC to
CO2, which is purged from the sample. Then a persulfate digestion is used to
convert DOC to DIC, which is converted to CO2 and transferred to He carrier.
-Bill

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Bill Holmes
UC-Davis Stable Isotope Facility
2220 Plant & Env Sci
One Shields Ave
Davis, CA 95616
Phone: (530) 752-8100
FAX: (530) 752-4361
stableisotopefacility.ucdavis.edu
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



-----Original Message-----
From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On Behalf
Of Amzad Hussain
Sent: Monday, April 07, 2008 12:04 PM
To: [log in to unmask]
Subject: [ISOGEOCHEM] stable isotopic measurement of DOC

Hi everyone
I would like to know how CO2 can be extracted from Dissolved Organic
Carbon for stable isotopic analysis?

Thanks
Amzad


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