Re: Peptide Content

peptide technologies corp. (peptech@access.digex.net)
Thu, 23 Jul 1998 09:36:17 -0400 (EDT)

A quantitative determination of free amino groups can give you the moles
of peptide. Trinitrobenzene sulfonic acid (TNBS) is reacted in aqueous
buffer above pH 7 to give a colored derivative with max at 335 to 345 nm
The ext. coef. is 1.4 X 104. The details of the method can be obtained in
Mean and Feeney, "Chemical Modification of Proteins"p.217 Holden-Day 1971.
They give the original ref. as Habeeb 1966 Anal. Biochem.14:328.
Best wishes,

Martha Knight
President
Peptide Technologies Corporation
phone 301 869-7306 Fax 301 869-7308

On Wed, 22 Jul 1998, Henry Wolfe wrote:

> Date: Wed, 22 Jul 1998 12:12:07 -0600
> From: Henry Wolfe <hnwo@americas.nycomed.com>
> To: Recipients of ABRF List <abrf@aecom.yu.edu>
> Subject: Peptide Content
>
> I am looking for a sensitive, linear, quantitative metod for determining
> peptide content. The restrictions I am under are the following: I have a
> 12-residue peptide with one primary amine, three disulfides and no
> aromatic amino acids. Also, I do not own an amino acid analyzer or
> protein sequencer, but have good UV, fluorescence, CE and HPLC
> equipment. Any suggestions? References to journal articles would be an
> added bonus.
>
> Thanks,
>
> Hank Wolfe
> henry.wolfe@nycomed-Amersham.com
>
>