pepsyn-HoBT/pip
Sandra Smith (sandie@mail.utexas.edu)
Fri, 15 May 1998 16:06:44 -0400 (EDT)
All you peptide synthesis experts, I need help. I've synthesized two
31mers, Fastmoc Chemistry, on a ABI 430. They both had either consecutive
asps,(4)or a asp-asn sequence. I used .1M HoBT/20%pip in NMP to deprotect.
Kaiser tests showed no problems.AAcomps look good. I sequenced one and went
28 cycles before it washed out. The sequence was perfect. HPLC showed at
least 95% one peak for one; the other peptide had one large peak with a
high,very slight shoulder. The problem: MALDI showed two peaks for each
peptide, one the correct mass and the other about 115mu larger. I have no
idea what this is or what to do about it. My experience in pepsyn and mass
spec is very limited. Any help would be GREATLY appreciated. Thank you,
Sandie Smith
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