Weak binding of N-alkylpyridinium ions to nonionic surfactant micelles as studied by capillary zone electrophoresis.

The binding equilibrium of N-alkylpyridinium ions to nonionic surfactant micelles was investigated through the changes in the electrophoretic mobility of the alkylpyridinium ions in capillary zone electrophoresis. The binding constants thus determined increased with increasing molecular volume of the alkylpyridinium ions. However, the binding constants are small compared with the ones for the anionic alkylbenzenesulfonate and polynitrophenolate ions at the same molecular volume.