Chiral Membranes for Racemic Mixture Separation

A new method for racemic mixture separation by membrane processes taking advantage of chiral polymers and chiral ionic liquids is present. The supported chiral room temperature ionic liquid membrane is used for selective separation of enantiomers. Non-volatile enantiomers are separated by pertraction.

Despite enantiomers exhibit identical properties in the achiral environment, should be considered as different chemical compounds because they often differ tremendously in effectiveness, pharmacological activity and pharmacokinetic profile, since the modules with which they interact in biological systems are also optically active [1,2].

Racemic mixture of Tryptophan - D and L enantiomers - was chosen as the model substance. During pertraction experiments the membrane was placed between the feed and receiving phase of the pertraction cell; five types of membranes with immobilizing chiral selector (0-50% diamine cyclohexane in 1,3-diamine benzene) were used.

During pertraction experiments we find out, that kinetics of the pertraction significantly influence the enantiomer resolution what indicated that facilitated transport is employed.

Acknowledgement: This research was supported by the Czech Republic Foundation for grant No. 17-00089S.

Key Words: chiral membranes, racemic mixture, tryptophan, pertraction

[1] S.W. Smith, Chiral Toxicology, It's the Same Thing. Only Different. Toxicological Sciences (2009) 110 (1): 4-30.

[2] M.R. Islam, J.G. Mahdi, I.D. Bowen, Pharmacological importance of stereochemical resolution of enantiomeric drugs, Drug safety: an international journal of medical toxicology and drug experience (1997) 17 (3): 149-65.