Publication details
Electroosmotic Flow Changes Due to Interactions of Background Electrolyte with Polyethyleneimine Coating in Capillary Zone Electrophoresis of Proteins
| Authors | |
|---|---|
| Year of publication | 2006 |
| Type | Article in Periodical |
| Magazine / Source | Journal of Separation Science |
| MU Faculty or unit | |
| Citation | |
| Field | Analytic chemistry |
| Keywords | polyethyleneimine; capillary coating; electroosmotic flow; protein adsorption |
| Description | The properties and behavior of polyethyleneimine (PEI) covalently coated capillaries with respect to different background electrolytes used in capillary zone electrophoresis (CZE) is described. The coating stability and changes of inner surface charge in the capillary were followed by electroosmotic flow (EOF) measurement. The main interest was focused onto conjugate bases of carboxylic acids as anionic background electrolyte components (acetate, citrate, malate, malonate, tartrate and succinate). Interesting phenomenon in PEI coated capillaries was observed: the direction (and the magnitude) of EOF depends on the composition of the background electrolyte and at a certain pH it can reversibly change. To explain this behavior, a hypothesis of an ionic complex formation was suggested. With this knowledge, the PEI coated capillary was used for the separation of basic proteins in mentioned background electrolytes. As a model sample, a standard protein mixture of cytochrome c, ribonuclease A and lysozyme in concentration of 0.25 mg/ml each was chosen. |