Improvement of Separation in Non-Aqueous Capillary Electrophoresis using Surfactants and Calixarenes as Additives

In this study the effect of the presence of some different additives on non-aqueous capillary electrophoresis (NACE) separations of some structurally related compounds belonging to beta-blockers, antidepressants or neuroleptics were examined. Presence of surfactant was found to have a strong effect on separations. The anionic surfactant sodium dodecyl sulfate (SDS) enhanced separation of neuroleptics and beta-blockers. Upon combination between SDS and toctyl- calix[4]arene-tetra-ethylester (TOCXTEE) separation of beta-blockers could be optimized. Use of cyanomethylcalix [4]arene (CMCX[4]) with buffer including SDS for separation of neuroleptics elongated the separation time and had some positive and negative effects on separation. The cationic surfactant tetrabutylammonium-bromide (TBAB) was found to be better than that of SDS for the separation of antidepressants. Structure of analytes and calixarenes played an effective role in separation.