Polyelectrolyte complex films for analytical and membrane separation of chiral compounds
View Patent ↗The present invention is directed to enantioselective polyelectrolyte complex films. Further, said films may be free or isolated membranes, or coatings on substrates such a porous substrates, capillary tubes, chromatographic packing material, and monolithic stationary phases and used to separate chiral compounds. The present invention is also directed to a method for forming such enantioselective polyelectrolyte complex films.
1. A supported membrane, the supported membrane comprising a porous substratum having a surface and a polyelectrolyte complex film on the surface of the porous substratum, the polyelectrolyte complex film having a thickness between about 10 nm and about 10,000 nm and comprising a positively-charged polyelectrolyte and a negatively-charged polyelectrolyte, and at least one of the polyelectrolytes comprises an enantiomeric excess of chiral repeat units.
2. The supported membrane of claim 1 wherein the pores have an average pore size between about 100 nm and about 10 μm.
3. A chromatographic medium comprising:
a chromatociraphic stationary phase substratum having a surface, the chromatographic stationary phase selected from the group consisting of a porous particulate chromatographic packing material, a capillary tube, and a porous continuous solid;
and a polyelectrolyte complex film on the surface of the chromatographic stationary phase substratum, the polyelectrolyte complex film having a thickness between about 10 nm and about 10,000 nm and comprising a positively-charged polyelectrolyte and a negatively-charged polyelectrolyte, wherein at least one of the positively-charged polyelectrolyte and the negatively-charged polyelectrolyte comprises an enantiomeric excess of chiral repeat units.
4. A method of chromatographically separating test enantiomers, the method comprising contacting a solution comprising test enantiomers with a chromatographic medium comprising a stationary phase substratum having a surface and an optically active polyelectrolyte complex film on the surface of the stationary phase is phase×3 substratum, wherein
the stationary phase substratum is selected from the group consisting of a porous particulate chromatographic packing material, a capillary tube, and a porous continuous solid;
the optically active polyelectrolyte complex film has a thickness between about 10 nm and about 10,000 nm and comprises a positively-charged polyelectrolyte and a negatively-charged polyelectrolyte, wherein at least one of the positively-charged polyelectrolyte and the negatively charged polyelectrolyte comprises an enantiomeric excess of chiral repeat units; and
the test enantiomers interact with the polyelectrolyte complex film on the surface of the stationary phase in an enantioselective manner.
5. The method of claim 4 wherein the stationary phase substratum is the porous particulate chromatographic packing material.
6. The method of claim 4 wherein the positively-charged polyelectrolyte and the negatively-charged polyelectrolyte comprise an enantiomeric excess of chiral repeat units.
7. The method of claim 4 wherein the positively-charged polyelectrolyte and the negatively-charged polyelectrolyte comprise an enantiomeric excess of L-chiral repeat units or the positively-charged polyelectrolyte and the negatively-charged polyelectrolyte comprise an enantiomeric excess of D-chiral repeat units.
8. The method of claim 4 wherein the positively-charged polyelectrolyte and the negatively-charge polyelectrolyte are selected from the group consisting of linear polyelectrolytes, branched polyelectrolytes, dendritic polyelectrolytes, graft polyelectrolytes, comb polyelectrolytes, and copolymers thereof.
9. The method of claim 4 wherein the polyelectrolyte comprising an enantiomeric excess of chiral repeat units is formed from chiral monomer units.
10. The method of claim 9 wherein the polyelectrolyte comprising an enantiomeric excess of chiral repeat units is poly(lysine) or poly(glutamic acid).
11. The method of claim 4 wherein the polyelectrolyte comprising an enantiomeric excess of chiral repeat units is the reaction product of a non-chiral polymer and a chiral reagent or a non-chiral reagent which introduces chirality.
12. The method of claim 11 wherein the positively-charged polyelectrolyte is the polyelectrolyte comprising an enantiomeric excess of chiral repeat units and the non-chiral polymer comprises a quaternary ammonium group, an amine group, a pyridine group, or a benzyl halogen group.
13. The method of claim 12 wherein the chiral reagent or the non-chiral reagent which introduces chirality is selected from the group consisting of a chiral alkyl halide and a chiral aryl halogen.
14. The method of claim 11 wherein the negatively-charged polyelectrolyte is the polyelectrolyte comprising an enantiomeric excess of chiral repeat units, and the negatively-charged polyelectrolyte comprises a sulfonate group or a carboxylate group.
15. The method of claim 4 wherein at least one of the negatively-charged polyelectrolyte and the positively-charged polyelectrolyte comprises a chiral cyclodextrin moiety.