On Thu, 21 Jan 1999 colemanr@zgi.com wrote:
>
> Cameron-
>
> I too experience the black tar in certain hydrolyzed samples. Like Tom, I have
> not found it to interfere with derivatization or chromotography. However, a
> quick, low speed centrifuge will drop the tar from solution and away from your
> injector needle, or allow you to transfer the sample away should you so desire.
>
> Ryan Coleman.
>
>
> ______________________________ Reply Separator _________________________________
> Subject: Re: AAA hydrolysis
> Author: tandersen@ccgateway.amc.edu at smtpgate-zgi
> Date: 01/21/1999 2:35 PM
>
>
> Cameron-
>
> When running hydrolysis as you do, followed by Pico-Tag analysis, I
> encountered the black tar associated with high carbohydrate
> concentrations in the sample. I proceeded as normal with the
> derivitization and chromatography and generally obtained excellent
> results. The tar is quite insoluble and does not interfer too much
> with analysis. I have less information about recovery of amino acids.
> I suppose prudence would compel one to be sure the gaurd column is
> functional, but the tar may not be a dead end.
>
> Tom Andersen
>
>
> ______________________________ Reply Separator _________________________________
> Subject: AAA hydrolysis
> Author: cameron.olbert@arcb.us.astra.com at Internet-Mail
> Date: 1/20/99 3:30 PM
>
>
> Dear ABRF members,
> We are currently trying to do AAA on a protein in a 10mM Tris 1%
> n-Octyl-Glucopyranoside buffer and at the end of the hydrolysis step we are
> seeing a black mass coating the bottom of the sample tubes. We are running
> a vapor phase hydrolysis with 6N HCl 1% phenol, at 110C for 20 hours,
> purging the reaction vial with nitrogen before hydrolysis. We believe the
> black mass is caused by the nOG in the buffer (we've seen it in a buffer
> blank). Any suggestions on how to avoid this hydrolysis problem are greatly
> appreciated.
>
> Thank you in advance
> Cameron Olbert
> Astra Research Center Boston
> cameron.olbert@arcb.us.astra.com
>
>