SEPARATION OF HIGHLY HYDROPHOBIC COMPOUNDS BY CYCLODEXTRIN-MODIFIED MICELLAR ELECTROKINETIC CHROMATOGRAPHY

Cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC), in which CD is added to the micellar solution, was developed for the separation of electrically neutral, highly hydrophopbic compounds. The separation of such substances is generally difficult by electrophoretic techniques. In CD-MEKC, a water- insoluble hydrophobic solute is partitioned between the micelle and CD. When the solute is included in the CD cavity it migrates with the electroosmotic velocity, and when it is incorporated into the micelle it migrates with the micellar velocity. Accordingly, the differential partition of the solute between CD and the micelle enables a separation to be achieved. Highly hydrophobic and closely related compounds such as chlorinated benzene congeners, polychlorinated biphenyl congeners, tetrachlorodibenzo-p-dioxin isomers and polycyclic aromatic hydrocarbons have been successfully separated. © 1990.