Ken Fishbein wrote the following:
I response to Sean Xie's question about a uniformly 13C and
15N labeled small peptide standard, you can buy the octapeptide
HTyrGlyGlyPheLeuArgArgIleOH with the GlyPheLeu residues uniformly 13C
and 15N labeled as a 1mM solution in DMSO-d6 from Cambridge Isotope
Laboratories. It is their catalog number CNLM-2408 and costs $950
MSRP as of 1998. CIL's phone number is (800) 322-1174.
I purchased this sample a found out that it is not completely uniformly
labeled. The sequence YGGFLRRI is only labeled at GFL. This can be very
confusing when you are looking for eight nitrogen peaks and only see three.
If you do purchase this sample be sure the CIL sends you the standard
spectra that they have run for the sample.
Good luck,
Les
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Leslie Gelbaum Phone 404 894-4079
NMR Center Lab Phone 404-894-1827
Georgia Tech Fax 404 894-7452
Atlanta, Georgia 30332 E-mail lg2@prism.gatech.edu
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