> -----Original Message-----
> From: mcada002@mc.duke.edu [SMTP:mcada002@mc.duke.edu]
> Sent: Friday, September 17, 1999 9:19 AM
> To: Recipients of ABRF List
> Subject: Need ion exchange HPLC col's
>
>
>
> Can anyone recommend HPLC col's and buffers for purification of 50 to 100
> mg of
> peptides via ion exchange.
> Presently I need to purify two very short synthetic peptides (4 AA's).
> They
> will not interact (i.e., they wash through) with my C18 Reverse Phase
> columns in
> either 0.1%TFA, 0.1%HFBA, or 50 mM NH4HCO3. Sequence is
> NH2-Arg-Gly-(Asp/or
> Glu)-Ser-OH. Mol. Wt's 433.5 and 447.5.
>
>
> I have also had much difficulty with very long (30 AA's long), Asp/Glu
> rich
> peptides that did respond better with the 50mM NH4HCO3 and C18 column.
> But
> these shortties are just not gonna cooperate.
>
> Help, Help Help.
>
> Thanks.
>
> Millie
> mcada002@mc.duke.edu
> 919-684-2652
> 919-684-5458 FAX
>