抄録
A high performance liquid chromatography (HPLC) for cationics and carboxybetaine amphoterics in cosmetic products was developed with a cation-exchanger as a stationary phase. An aqueous methanol solution containing glycine-perchloric acid salt was used as a mobile phase.
Cationics were retained in the whole range of the mobile phase pH, whereas amphoterics were retained only below pH 4. The order of elution in homologous species was related to its organic moiety and the elution time decreased with increasing carbon numbers of the solute. The ion-exchange mechanism was confirmed to be operative in this separation.
As this chromatography retained only cationic or carboxy betaine amphoteric species, it would be suitable for a quality control of cosmetic products containing them.
