Enantiomeric separation of chiral polychlorinated biphenyls by micellar electrokinetic chromatography using mixtures of bile salts and sodium dodecyl sulphate with and without ?-cyclodextrin in the separation buffer

The possibilities of using bile salts alone and mixed with sodium dodecyl sulphate (SDS) in micellar electrokinetic chromatography (MEKC) to achieve the enantiomeric separation of chiral polychlorinated biphenyls (PCBs) have been studied. In these conditions, only three (IUPAC numbers 84, 95, and 176) of the nineteen chiral PCBs stable at room temperature were enantiomerically separated. However, up to fifteen chiral PCBs were separated, each one in its two enantiomers, when a chiral additive as γ-cyclodextrin (γ-CD) was added to the separation buffer which contained a bile salt (sodium cholate, SC) and SDS. The influence of γ-CD concentration on the enantiomeric resolution of all chiral PCBs stable at room temperature was studied using buffers containing a mixed micellar system SC/SDS. Enantiomeric separations of multicomponent mixtures of chiral PCBs were also performed using a 0.1-M 2-(N-cyclohexylamino)-ethanesulphonic acid (CHES) buffer (pH=9), 0.05-M SC/0.05-M SDS, and 0.05-M γ-CD. Mixtures of up to eight PCBs were baseline separated into all their sixteen enantiomers in only 35 minutes.