you might try KCl and thus generate the potassium adduct and thus strengthen
the argument (I am sorry if this is a dumb suggestion - I don't know if KCl
interferes with MALDI!!) Best of luck - alex
----- Original Message -----
From: "Bart Haigh" <bart.haigh@ipd-discovery.com>
To: "Recipients of ABRF List" <abrf@aecom.yu.edu>
Sent: Friday, August 25, 2000 10:52 AM
Subject: Na adduct in Maldi
> I have been using a synthetic peptide (nh2) RVYIHPFHL (cooh) in a reaction
> mixture which contains .2M Na+Po4 and have been unable to dialyze the
sodium
> out or exchange it with K+.
> I always get a 100% modified peptide with + 22 when glucose is added to
the
> mixture and only a small amount of the +22 adduct when no glucose is in
the
> mixture . I have been using alpha-cyano as a matrix and have heard it
may
> contain sodium but the extent of sodium modification of the peptide
without
> glucose is far less than with glucose . I was wondering does anyone know
of a
> sure way to displace the Na+ to allow us to be sure it is a sodium
adduct
> (unfortunately we can not run the reaction without sodium it must be
removed
> afterwards). Thanks for any help,
>
> Bart Haigh
>
>
>
This archive was generated by hypermail 2b29 : Fri Sep 01 2000 - 16:10:38 EDT