This title appears in the Scientific Report :
2006
Please use the identifier:
http://dx.doi.org/10.1002/elps.200500673 in citations.
Nonaqueous versus aqueous capillary electrophoresis of alpha-helical polypeptides: Effect of secondary structure on separation selectivity
Nonaqueous versus aqueous capillary electrophoresis of alpha-helical polypeptides: Effect of secondary structure on separation selectivity
The CE separation of alpha-helical polypeptides composed of 14-31 amino acid residues has been investigated using aqueous and nonaqueous BGEs. The running buffers were optimized with respect to pH. Generally, higher separation selectivities were observed in nonaqueous electrolytes. This may be expla...
Saved in:
Personal Name(s): | Psurek, A. |
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Feuerstein, S.E. / Willbold, D. / Scriba, G. K. E. | |
Contributing Institute: |
Biologische Strukturforschung; IBI-2 |
Published in: | Electrophoresis, 27 (2006) S. 1768 - 1775 |
Imprint: |
Weinheim
Wiley-Blackwell
2006
|
Physical Description: |
1768 - 1775 |
DOI: |
10.1002/elps.200500673 |
PubMed ID: |
16645940 |
Document Type: |
Journal Article |
Research Program: |
Funktion und Dysfunktion des Nervensystems |
Series Title: |
Electrophoresis
27 |
Subject (ZB): | |
Publikationsportal JuSER |
The CE separation of alpha-helical polypeptides composed of 14-31 amino acid residues has been investigated using aqueous and nonaqueous BGEs. The running buffers were optimized with respect to pH. Generally, higher separation selectivities were observed in nonaqueous electrolytes. This may be explained by a change in the secondary structure when changing from water to organic solvents. Circular dichroism spectra revealed a significant increase in helical structures in methanol-based buffers compared to aqueous buffers. This change in secondary structure of the polypeptides contributed primarily to the different separation selectivity observed in aqueous CE and NACE. For small oligopeptides of two to five amino acid residues no significant effect of the solvent was observed in some cases while in other cases a reversal of the migration order occurred when changing from aqueous to nonaqueous buffers. As these peptides cannot adopt secondary structures the effect may be attributed to a shift of the pKa values in organic solvents compared to water. |