RE-????

Tom Haas Ph.D. (haast@cesmtp.ccf.org)
Tue, 29 Sep 1998 11:54:40 -0400

I have a problem with the below sugestion from Leah Efron. If you check
out paper by Werner WE, Demorest DM, Wiktorowicz JE: Analysis of
residual TFA in synthetic peptides. Biotechniques 1995;78 (pgs ?) you
will see that acetic acid will not replace TFA but that HCl will. Even base
solutions will not remove the TFA. I redissolve my peptides in 50-100 mM
HCl, freeze and the dry in a speed vac. This replaces TFA salt with a Cl
salt.

Tom Haas
Molecular Cardiology
Cleveland Clinic
haast@cesmtp.ccf.org

>>> "Leah Efron" <uunet!leah@mail.uu.net> 09/28/98 06:47pm >>>
Responding to the message of Mon, 28 Sep 1998 09:01:38 +0200
from Karolina.Lawitz@draco.se.astra.com:

Dear, Karolina
In our laboratory we change the TFA salt in peptide to acetate salt by
dissolving of peptide TFA salt with Acetic acid:TDW (1:1) and liophelaze
this mixture. >

Leah Efron
leah@vms.huji.ac.il.
Hi
> Does anyone know a way to exchange TFA salt in petides with other
> salts then Cl or acetate ?
> Thanks in advance,