Hi, Steve:

Our lab have handled hundreds of biological fluids including blood plasma
samples in the past several years. The problem is the protein and other organic
in the sample. If you distill the samples, you may be able to treat them like
normal water for D/H analysis. Otherwise, you may see the D/H ratio changing as
time goes by. You may want to use double amount of zinc if you don't want to
distill the water and run the sample right away. The activated zinc from our
own lab (called GGC zinc) can handle brines and biological samples pretty well.
Contact me if you are interested in that.

Regards.

Dachun Zhang
Isotope Lab
ZymaX

Steven Beaupre wrote:

> Greetings all;
> We are currently reviewing techniques for the preparation of deuterium
> samples from water in biological samples (blood plasma).  In a recent read
> of Speakman, J. R. 1997. "Doubly Labelled Water: Theory and Practice." two
> issues have arisen that I'd like to get some advice on.  Thanks in advance
> for any help you can supply.
>
> 1) On page 270, Speakman suggests that when using the zinc reduction
> method, the water sample and the zinc should be kept separate until the
> reaction vessel is close to reaction temperature.  Furthermore, he states
> that allowing the two to come in contact at room temperature "affects the
> reaction".  Unfortunately, he provides no reference for this observation.
> Can someone enlighten me about this effect, and whether keeping the water
> and zinc separate is a necessary procedure?
>
> 2) Also on page 270, Speakman suggests that there is an open question about
> whether water from blood plasma or urine needs to be distilled from the
> sample prior to reduction with Zinc.  He provides ample references
> regarding the debate as it stood in 1997, however, I'm interested in
> knowing if a definitive answer has materialized.  Does anyone know of a
> relevant reference?
>
> Thanks.
> Steve Beaupre
>
> ===================================
> Steven J. Beaupre
> University of Arkansas
> Department of Biological Sciences
> Ferritor Building, B2
> Fayetteville, AR  72701
>
> Phone: 501-575-7561
> Fax:  501-575-4010
> email: [log in to unmask]
> Web: http://comp.uark.edu/~sbeaupre/beaupre.html