Hi Everyone,

I am working in a stable isotope lab that is just getting its feet on the
ground.   At present it appears that we will mostly be working with
biological material (fish tissue, insects, leaves, feathers, etc) and
analysing for C, N & S.  Samples will be oven or freeze dried before
grinding.   My questions relate to the grinding end of things:

We have access to two 8000 Spex Certiprep mills and would like to be able
to use these for sample grinding.  I have 2 questions:

- Does anyone have experience with these mills and their performance?

- What about grinding vials.  The choices seem numerous: stainless steel,
agate, zirconia, alumina ceramic, tungsten carbide....    We want a vial
that adds as little contamination as possible to our sample, one that
isn't too brittle (since there will be many users and vial breakage will
be a real concern), and one that isn't too expensive (if possible).  I
know that  stainless steel contains some S and tungsten carbide some C
but our sample material, being biological, is quite soft and shouldn't
abrade the container too much so maybe contamination isn't a concern.  On
the other hand agate & alumina ceramic shouldn't pose a problem w.r.t.
contamination (hard and little if any C,N or S) but both are quite
brittle and prone to chipping/breakage.  Zirconia seems a suitable option
(not brittle and little worry about contamination) but it's very pricey.
Can anyone comment as to which vial type they use and why?

Thanks in advance for any information,
Evelyn Stillwell

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Evelyn Stillwell
Department of Biology
University of New Brunswick
Bag Service Number 45111
Fredericton, N.B.
E3B 6E1

Phone:(506) 453-4583
Fax: (506) 453-3583
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