Separation of natural and synthetic heparin fragments by high-performance capillary electrophoresis

The application of capillary electrophoresis (CE) for the analysis of natural and synthetic low-molecular-mass heparin fragments at low pH is described. It is demonstrated that under the applied conditions the separation is based on charge, charge distribution and molecular mass of the heparin molecules, yielding a high resolution. It is shown that the presence of sodium chloride in the sample solution has hardly any effect on the CE performance. However, the pH of the electrophoresis buffer is a critical parameter. The resolutions obtained with CE and high-performance anion-exchange chromatography (HPAEC) are compared for various heparin fragments and it is concluded that, at least for this type of molecule, CE forms an attractive alternative to HPAEC.