ENANTIOSELECTIVE TRANSPORT OF AMINO-ACID THROUGH SUPPORTED CHIRAL LIQUID MEMBRANES

Two chiral alcohols, nopol and (2S)-(-)-methyl-1-butanol, immobilized in the pores of a polyethylene film were used for the enantioselective transport of amino acid hydrochloride. The degree of stereoselectivity of the permeation process varied from 0.39 to 1.52 depending on both the type of the chiral membrane phase and the properties of the amino acid. The evaluation of the membrane ability to separate stereoisomers was performed by the step-by-step analysis by considering the effect of amino acids' hydrophobicity, polarity and degree of chirality. For the purpose of this paper, the chirality measure was introduced. It was demonstrated that the enantioselectivity was affected mainly by the degree of chirality, and that the nopol membrane was the most efficient one.