We just made a flourescein peptide, labelled at the Lys side chain via
Lys(Mtt).
We coupled flourescein free acid (4eq) with HATU (4eq), HOAt(4eq),
DIEA(6eq) in DMF over night. Ninhydrin test showed a green colour, resin
beads were white. The flourescein coupled according to MS. No
[M-flourescein] peak in the spectrum.
I hope this helps.
Henriette
>we have been trying to label the following peptide on the n-term with
>Fluorescein.
>
>Y G R K K R R Q R R R G K P P A P P M R N T S T M
>
>Before labeling, we did a partial cleavage to make sure we made the intact
>peptide and it looks great.
>
>We tried using FITC followed by washing and cleaving. We end up with ONLY
>the peptide - Y. I figure I must be going through an edman type cleavage
>during cleavage and deprotection even though we keep it pretty cool. (I
>know some are saying DAH!)
>
>We then used Fluorescein-NHS. Most of our product is unlabeled (90%) and
>then there is a product that is that is -17 amu.
>
>What is your favorite protocol for labeling with Fluorescein?
Henriette A. Remmer, Ph.D.
Director, Protein Sciences Facility
Biotechnology Center
University of IIllinois
315/311 Noyes Laboratory, Box 62-1
505 S Mathews Ave Urbana, IL 61801
phone: (217)333-4695 (lab) or (217) 333-3841 (office)
fax: (217)244-1142 email: remmer@uiuc.edu
homepage: http://www.life.uiuc.edu/biotech/protein_sc.html
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