We found some years ago that maybe peroxides could be formed in the
THF
eluting solvent of our 477A-120A sequencer, thus decreasing the recovery
of lys.
Some hardware and software modifications were made in the sequencer for
argon
pumping into the THF bottle, so that the problem was solved. Maybe your
ethyl
acetate or other solvent is also being contaminated by peroxides. Please
have a
look at our paper below:
Fontes, W., Cunha, R.B., Sousa, M.V. and Morhy, L.M. (1998).
Improving the
recovery of lysine in automated protein sequencing. Analytical
Biochemistry 258,
259-267.
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Prof. Marcelo Valle de Sousa
Brazilian Center for Protein Research and Services - CBSP
Laboratory of Biochemistry and Protein Chemistry
Departament of Cell Biology
University of Brasilia
Brasilia - DF Brazil
CEP 70910-900
Tel: (061)307-2142
Fax: (061)272-4548
e-mail: mvsousa@unb.br
http://www.unb.br/cbsp
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