Separation of cimetidine and related materials by aqueous and non-aqueous capillary electrophoresis (vol 808, pg 269, 1998)

Capillary electrophoresis (CE) has been shown to be a highly efficient separation method well suited to the analysis of pharmaceutical products. The separation of impurities and degradation products from the compound of interest often requires the high resolving power of which CE techniques are capable. The majority of reported separations have been performed in aqueous media. However, the addition of small amounts of organic modifier may be used to effect changes in selectivity and improve resolution. Recent reports have suggested that the use of completely non-aqueous separation media allow improved selectivity and are beneficial for the analysis of hydrophobic materials. To investigate this we have undertaken the separation of a drug substance and a series of associated impurities and degradation products using both aqueous and non-aqueous media. The data obtained clearly indicates that highly efficient separations may be accomplished in non-aqueous systems and that analysis of hydrophobic materials becomes possible. Selectivities and efficiencies for the separations are described indicating that complementary information can be obtained.