Re: HPLC

Amos Heckendorf (nestgrp@world.std.com)
Wed, 3 Mar 1999 18:02:52 -0500

>Hi, all
>Has anyone ever used a Brownlee CX-300 column? I have one for my old
>ABI 120 microbore--and would like to try some cation exchange to
>separate a peptide from an 18,000 dalton, pI of 11, protein. What is a
>suggested mobile phase? Is 20 mM phosphate pH 5.5, with a gradient up to
>0.2 M NaCl a good mobile phase? I want to look at 220nm as the peptide
>has no aromatics,

Deb McMillen:

That will be a good place to start for that column. If there aren't two to
three positive charges on the peptide though, it might not stick.

You could move the pH up a little to pH 6.5 to be sure all the carboxyls
are ionized on the packing, especially if you are looking for retention of
the peptide too. With a pI of 11 it might take much more salt to get the
protein off. Try 0.5M instead.

Sincerely,
Amos Heckendorf

Amos Heckendorf (nestgrp@world.std.com)

The Nest Group, Inc., Value Added Resellers of HPLC Columns (Vydac(tm),
PolyLC(tm), BioChrom Hydrocell(tm), Jordi-Gel(tm), Macherey-Nagel
Nucleosil(tm), Higgins Analytical HAISil(tm),TARGA(tm) & CLIPPIUS(tm), and
Bischoff Prontosil(tm)) Genomic Solutions(tm) PAGE gels; Amika COZAP
Destaining pads, Dispo-BioDialyser(tm) and ProTip(tm) MS MicroSample SPE
Tips; and KronLab BioCart(tm) glass adjustable columns. Tel: 800-347-6378
or 508-481-6223; FAX 508-485-5736;
45 Valley Rd, Southboro, MA 01772-1306
Applications and Protocols at:
HTTP://world.std.com/~nestgrp/protocols/protocol.html