Thioglycolic acid is the same as mercaptoacetic acid. It is the thiol derivative of glycolic acid (hydroxy acetic acid).
I think the protective action of this agent is due to its being a small, charged, thiol-containing molecule that would migrate faster than any protein or peptide on the gel. The mercaptoacetate ions would scavenge unpolymerized acrylamide (or radical species?) before the protein or peptide could react with them.
Way back in graduate school, I would add mercaptoacetic acid to my sensitive protein samples before loading them, to eliminate gel-induced artifacts. I'd even use it in native electrophoresis, and afterwards be able to stain the gel for activity, so it's a relatively innocuous reagent.
Vernon
Vernon A. Shoup
Regeneron Pharmaceuticals
Rensselaer, NY 12033
(518)488-6012
vernon.shoup@regpha.com
--------------------------------------
Date: 5/19/98 8:14 PM
From: Helene Hill
Would thioglycholate be just as good as mercaptoacetic? I'm new at this:
what do you mean that the protein is blocked in the 1st dimension gel?
On Tue, 19 May 1998, Suming Hua wrote:
> Prerun gel at 90 volts in your buffer, the uper buffer should contain > mercaptoacetic acid, sodium salt (0.2g in 300 ml buffer) or other
> reducing reagent, for 30 min, then run your sample. The protein should be
> protected from becoming blocked.
> > On Mon, 18 May 1998, Sandra Smith wrote:
> > > Dear Members,
> > > > We have a user who is wondering what can or should be done to protect
> > proteins from becoming blocked in the 1st dimension gel. We prerun our 2nd
> > dimension gels and age them to insure complete acylamide polymerization,
> > but we are unfamiliar with precautions for the 1st dimension. Any advice
> > would be greatly appreciated.
> > > > Michelle Gadush and
> > > > Sandie Smith
> > Protein Microanalysis Facility,
> > Institute for Cellular and Molecular Biology
> > University of Texas, Austin, Texas 78712
> > Email: sandie@mail.utexas.edu
> > Phone: 512 471-3741, Fax: 512 471-2149
Helene Z Hill, Ph.D. Internet: hill@umdnj.edu
Head, Section of Cancer Biology Voice/fax: (973)972-3421
Mail: MSB-E586
NJ Medical School
185 South Orange Ave Newark, NJ 07103-2714
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Date: Tue, 19 May 1998 14:40:42 -0400 (EDT)
From: Helene Hill <hill@umdnj.edu>
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