AFFINITY CAPILLARY ELECTROPHORESIS EMPLOYING IMMOBILIZED GLYCOSAMINOGLYCAN TO RESOLVE HEPARIN-BINDING PEPTIDES

A new capillary electrophoresis technique has been developed for the a ffinity resolution of synthetic heparin-binding peptides using an immo bilized glycosaminoglycan. Heparin and heparan sulfate were immobilize d onto fused silica capillaries using biotin-neutravidin conjugation. These capillaries exhibited markedly reduced electroosmotic flow and w ere able to distinguish peptides based on the heparin binding domain o f acidic fibroblast growth factor (residues 125-144, GLKKNGSCKRGPRTHYG QKA) that differed only in the stereochemistry of the proline amino ac id residue. The peptide based on the native sequence was retarded comp ared to the peptide having unnatural stereochemistry, consistent with its stronger interaction for immobilized glycosaminoglycan. Improved r esolution is also obtained for additional arginine and lysine containi ng heparin-binding peptides.