The Open Analytical Chemistry Journal

2009, 3 : 16-21
Published online 2009 September 25. DOI: 10.2174/1874065000903010016
Publisher ID: TOACJ-3-16

Binding of Low-Molecular-Weight Cationic Ligands to Chondroitin Sulfate as Studied by Capillary Electrophoresis Frontal Analysis

Jesper Østergaard*, Perveen , Henrik Jensen , Claus Larsen and Claus Larsen
Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.

ABSTRACT

The feasibility of capillary electrophoresis frontal analysis for the study of low-molecular-weight ligandchondroitin sulfate interactions was investigated. The interaction of the 7 cationic ligands (lidocaine, propranolol, scopolamine, N-methyl scopolamine, N-butyl scopolamine, 2-propylisochinolinium, and methyl viologen) with the glycosaminoglycan chondroitin sulfate was investigated in 0.067 M phosphate buffer, pH 7.4, at 25oC. A frontal analysis method with a short analysis time, suitable for ranking ligands according to degree of complexation for chondroitin sulfate was developed. The double charged ligand methyl viologen possessed the highest affinity for chondroitin sulfate. Linear binding isotherms were obtained and apparent association constants were determined. Capillary electrophoresis frontal analysis may be an attractive tool for characterization of ligand-glycosaminoglycan interactions.

Keywords:

Affinity capillary electrophoresis, chondroitin sulfate, complexation.