>We are presently using the CE "anhidronie" that comes from Italy, it comes
>out of sealed bottles.  How do you clean it up, in a air drying oven at 65
>degrees C?  In a vacuum oven?
>We buy our other expendable chemicals from COSTECH, they seem to be pretty
>good.  Have you had trouble with Bruno?


I don't try to regenerate the anhydrone. Once it's spent I pitch it. I use
it new out of the sealed bottles.

I personally have not had any experience with Costech stuff, but I have
heard of people getting bad batches of chemicals from them. That is why I
always spent the extra money to get Carlo-Erba stuff from Italy (ie it was
expensive but I had never heard of any problems with it). Then, I recently
(a couple of months ago) got a bad batch of anhydrone from Carlo-Erba via
CE Elantech in NJ, methinks it has something to do with the switch from
Fisons to Thermo (at least as far as Carlo-Erba is concerned). When I had
the tailing problem I was using a new bottle of "Thermo" Carlo-Erba
anhydrone, when I switched to an earlier older bottle of "Fisons"
Carlo-Erba Anhydrone -the tailing miraculously disappeared. Evidently the
guys at CE were aware of the problem, but since most users are CHN types
they let it slide. I have since switched to Microanalysis anhydrone and
have not had any problems (at least with the current batch). I had heard
through the grapevine though, that several years ago someone had gotten a
bad batch of chemicals from them as well. Now I assume that every single
supplier that I am aware of has had a bad batch of chemicals (they probably
all get the stuff from the same manufacturer), so it is pretty much a toss
up of which is best, -you pays your money and you takes your chances.  I
have also heard of people using an individual supplier for years without
mishap, (they must be luckier than I). Personally, I can't afford to track
down problems associated with faulty chemicals, there are enough potential
things that can screw up in mass spectrometry, than to have the things you
assume will work, -not working! If you have done everything else you can
think of, and still have the tailing problem, I suggest you buy some new
anhydrone (from Microanalysis or whoever) and try it, if this fixes your
tailing problem you owe me a cold one! I would'nt be a bit surprised to
find that your bottle of CE anhydrone is from the same batch as my faulty
bottle of CE anhydrone. Keep me informed, I'm curious.

My best,

Douglas "Cap" Introne
Research Associate Professor/Laboratory Director
Stable Isotope Laboratory
Sawyer Environmental Research Center
University of Maine
Orono, ME 04469

Tel. (207) 581-2192
Fax (207) 581-3490
E-mail [log in to unmask]