Re: peptide solubility -Reply (fwd)

John Stewart (John.Stewart@UCHSC.edu)
Wed, 17 Sep 1997 08:19:57 -0600 (MDT)

Here is a copy of the message I sent to Dr. Yadav on solubilizing
hydrophobic peptides.
The amyloid peptides are notoriously insoluble, and it is not to
be expected that a reasonable concentration can be obtained in water. In
the literature you can read a horror story in which some investigators
injected amyloid peptides into the brain in HPLC solvent (MeCN-TFA)!

---------- Forwarded message ----------
Date: Tue, 16 Sep 1997 09:01:57 -0600 (MDT)
From: John Stewart <stewartj@essex.UCHSC.edu>
To: "Satya Yadav Ph.D." <YADAVS@cesmtp.ccf.org>
Subject: Re: peptide solubility -Reply

Dear Dr. Yadav:
Try the following:
1. Dissolve the peptide in a suitable amount of glacial acetic acid
2. Prepare a 1% solution of dextran (MW around 100,000) in water.
3. Dilute the peptide solution, with mixing, with the dextran solution.
Use an amount of dextran so that the final working concentration of
peptide will contain not more than 1% dextran.
4. Aliquot the solution in appropriate vials and lyophilize.
When the lyophilized powder is dissolved, you should get a clear
solution. You should be able to dissolve in physiological salt solution
at this point for use. Use as a control a solution containing the samae
concentration of dextran, to be sure there is no artifact produced.

John M. Stewart, Department of Biochemistry
Univ. of Colorado Medical School, Denver, CO 80262
Phone: 303-315-7534; FAX: 303-315-8215
Email: John.Stewart@UCHSC.edu

On Tue, 16 Sep 1997, Satya Yadav Ph.D. wrote:

> Dear Dr. Stewart,
>
> Many thanks for your message. This peptide will be used in the
> biological system We are looking for a sovent that can be diluted out
> after intial solubilization. We will give a try to your procedure.
>
> Satya Yadav
> Molecular Biotechnology Core
> Cleveland Clinic Foundation
> Tel 216-445-7095
>
>