PepSyn: FITC and NBD stability

David Andreu (andreu@admin.qo.ub.es)
Wed, 18 Feb 1998 18:52:43 +0100

For the labelling experts:
A customer has requested a peptide in two versions labeled at the N-terminus
with either fluorescein or NBD (7-nitrobenzo-2-oxa-1,3-diazole). I have two
questions:

1. In your experience, which is the best way to couple each fluorophore? The
customer suggests the isothiacyanate (FITC and NBD-ITC, respectively). Is any
of you familiar with those or can you suggest a better alternative?

2. What kind of acid stability do these labels have? We can use either Boc
(HF) or Fmoc (TFA) chemistry, but were successful with Boc chemistry before
with the unlabelled peptide. Any advice on that?

I am aware that similar questions have been asked before from the relatively
few experts in the list. I am sorry for the reiteration. Thanks in advance for
your advice. Best regards,

I recall this type of questions being asked in the past, and

David Andreu
Universidad de Barcelona
Depto. Quimica Organica
Tel/Fax: 402 1260
E-mail: andreu@admin.qo.ub.es