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Michael Jobling University of Melbourne
Ph.D. student Parkville
Australia 3052
Department of Pathology Ph: (+613) 9344 5874
Fax: (+613) 9344 4004
School of Chemistry Ph: (+613) 9344 7272
Fax: (+613) 9347 5180
e-mail: m.jobling@pathology.unimelb.edu.au
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>From: Jos Raymackers@INNOGENETICS on 03/05/98 09:52 AM
>
>
>To: ABRF questions
>cc:
>Subject: AAA
>
>
>Hello abrf'ers
>
>
>We have a serious problem concerning determination of the exact
>concentration of a protein sample. Up to now we always used AAA for this
>purpose. We perform PTC-analysis on a 420A/H (PE-ABI) automatic
>hydrolysis and ptc-derivatisation unit.
>Calibration is done by the "hydrolysis test peptide (PE-ABI, part
>no.400909) without the addition of a internal calibrant. The last few
>months we observed a real problem in the solubility of this hydrolysis test
>peptide. The result of this is that we normally have a very good
>compositional error for proteins (average below 10% error) BUT we are not
>sure anymore about the exact concentration of the measured protein batch.
>We contacted already the people from PE-ABI and they send us different
>hydrolysis test peptide batch numbers but the problem still exist.
>So, my questions :
>1. Has anyone already observed this problem with the hydrolysis test
>peptide on the 420A/H machine?
>2. Is there an alternative compound available as calibration compound in
>AAA?
>2. Is there a better way to determine the EXACT concentration of a protein
>batch? (no coloring method like BRADFORD, BCA, ...)
>
>Thanks in advance
>
>
>
>
>Jos Raymackers, Ing.
>
>
>
>e-mail (innogenetics) : josray@innogenetics.be
>
>e-mail (home) : jos.raymackers@village.uunet.be
>
>
>
>INNOGENETICS NV
>
>Industriepark 7 box 4
>
>9052 Zwijnaarde Ghent
>
>Belgium
>
>tel. (office) : 0032-9-2410778
>
>tel. (lab) : 0032-9-2410775
>
>fax. : 0032-9-2410907