RE: Mass analysis of uncharged peptide

Amina (amina@welchlink.welch.jhu.edu)
Fri, 27 Mar 1998 13:37:38 -0500

If you have enough sample, dissolve a little in Ammonium bicarbonate (25-100 mM pH 8.5), and assay by MALDI, or if you don't have enough, just add 0.3 ul of the supernatant of a saturated ammonium sulfate solution to your sample on the probe before you add the matrix. If the peptide is very hydrophobic dissolving it in 30-50% formic acid sometimes help.

Amina

Amina S. Woods, Ph.D.
Johns Hopkins School of Medicine
725 N Wolfe St., Baltimore, MD 21205
Tel: (410) 614-4981, Fax: (410) 955-3420
E-mail: amina@welchlink.welch.jhu.edu

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From: JGB@shcc.org [SMTP:JGB@shcc.org]
Sent: Wednesday, March 25, 1998 12:27 PM
To: Recipients of ABRF List
Subject: Mass analysis of uncharged peptide

Hello ABRF members!

I have a peptide which is competely without charge. The sequence contains the
amino acids Gly, Ala, and Thr, and the N and C termini are capped (Ac- and
-NH2, respectively). The mass is expected to be 2352. Any ideas on what would
be the best way to analyze if this peptide I've made has the right mass? Any
help would be greatly appreciated.

Thank You,

Jim Bann
Shriner's Hospital
Portland, OR.