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In the present study, the enantiomeric forms of hydrophobic amino acids ( l -tryptophan, l -tyrosine, and l -phenylalanine) were separated by molecularly imprinted capillary columns (MICC) via Capillary Electrochromatography (CEC) for the first time. The monomer ratio, crosslinker ratio, template molecule ratio, the porogen ratio and type, polymerization time, and also the effect of temperature were examined to increase the permeability properties of MICC. FTIR, SEM and BET analyses were realized for the characterization of MICC. The effect of the electric field, organic solvent ratio, and pressure were carried out experimentally to determine the optimum conditions. The separation performances of MICC and the non-imprinted capillary columns (NICC) were compared electrochromatographically.

Recognition mechanism and enantiomerically separations of the chiral compounds are subjects that always stimulate the great interest of researchers in pharmacology and natural sciences, who are interested in finding solutions for both analytical purity and preparative purposes. Capillary Electrophoresis has become one of the most important analytical approaches for enantiomeric separations due to its superior properties, such as high resolution and high efficiency of chiral selectors. In this field, where researchers continue to be interested, the distinctions continue to develop day by day, with the introduction of new techniques developed on the basis of Capillary Electrophoresis philosophy in parallel with the development process of technology, as well as the chiral selectors of many different forms. In this review, besides some descriptive theoretical information about capillary electrophoresis and the techniques associated with it, studies on chiral separations using different chiral selectors or different chiral additives, such as molecularly imprinted polymers, cyclodextrins, Metal-organic frameworks, ionic liquids, nanoparticles and monoliths in the last nearly 10 years (2010-2020) were examined.

A dopamine-imprinted monolithic column was prepared and used in capillary electrochromatography as stationary phase for the first time. Dopamine was selectively separated from aqueous solution containing the competitor molecule norepinephrine, which is similar in size and shape to the template molecule. Morphology of the dopamine-imprinted column was observed by scanning electron microscopy. The influence of the organic solvent content of mobile phase, applied pressure and pH of the mobile phase on the recognition of dopamine by the imprinted monolithic column has been evaluated, and the imprinting effect in the dopamine-imprinted monolithic polymer was verified. Developed dopamine-imprinted monolithic column resulted in excellent separation of dopamine from structurally related competitor molecule, norepinephrine. Separation was achieved in a short period of 10 min, with the electrophoretic mobility of 5.81x10(-5)m(2)V(-1)s(-1) at pH 5.0 and 500mbar pressure.