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Updated: May 13, 2026
12:27
Polyelectrolyte Complex for Heparin Binding Domain Osteogenic Growth Factor Delivery
Published on: August 22, 2016
Counterion condensation on heparin oligomers
Burcu Baykal Minsky1, Anand Atmuri, Igor A Kaltashov
1Department of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA.
Biomacromolecules
|March 6, 2013
Summary
Heparin
Area of Science:
- Biophysics
- Polymer Science
- Biochemistry
Background:
- Heparin exhibits a broad mobility distribution in electrophoresis.
- Heparin's mobility distribution is skewed, unlike uniformly sulfated chains.
- Partially degraded heparin shows higher mobilities than native heparin.
Purpose of the Study:
- Investigate the electrophoretic behavior of chain-length monodisperse heparin oligomers.
- Determine the relationship between heparin oligomer mobility and contour length.
- Explain the anomalously high mobility of native heparin.
Main Methods:
- Electrophoresis of native heparin and heparin oligomers.
- Mass spectrometry of heparin chains.
- Comparison with poly(styrene sulfonate) oligomers.
Main Results:
- Heparin oligomer mobility inversely correlates with the logarithm of contour length (L) for L=3-10 nm.
- Mobility reaches an asymptotic limit for L > 20 nm.
- Polyelectrolyte end-effect theory quantitatively explains observed mobilities.
Conclusions:
- Chain termini and sulfation domain interfaces reduce counterion condensation, explaining heparin's high mobility.
- End effects and junction effects influence heparin's electrophoretic behavior.
- These effects are crucial for understanding heparan sulfate biofunctionality.
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