Compositions and methods for selectively binding amines or amino acid enantiomers over their counter-enantiomers
AssigneeIBC Advanced Technologies, Inc.
InventorsRonald L. Bruening, Krzysztof E. Krakowiak
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Abstract
Naphthyl crown ether ligand molecules containing at least two naphthyl groups that are covalently bonded to suitable solid supports and coated by hydrophobic organic solvents are disclosed. These compositions and associated methods are characterized by selectivity of desired amine or amino acid enantiomers over their counter-enantiomers and derivatives. The composition preferably has an α-value greater than or equal to 4. This allows for the separation of such enantiomers with nonchromatographic resin bed separations of three separation stages or less.
Claims17
A method for concentrating, removing, and separating an amine or amino acid enantiomer from its counter-enantiomer from a source solution containing an enantiomeric mixture comprising the steps of:
- (a) contacting the source solution having a first volume with a composition comprising at least one ligand covalently bonded to a particulate solid support through a hydrophilic spacer having the formula:
- SS—A—X—L
- wherein SS is a porous or non-porous particulate inorganic or organic polymer solid support, A is a covalent linkage mechanism, X is a hydrophilic spacer grouping, L is a bisnaphthyl crown ether ligand molecule having at least two naphthyl groups, wherein SS—A—X—L is coated with a hydrophobic organic solvent with the proviso that when SS is a particulate organic polymer, A—X may be combined as a single covalent linkage, and wherein the L portion of the composition has an affinity for a desired amine or amino acid enantiomer over its counter-enantiomer such as to form a complex between the desired amine or amino acid enantiomer and the ligand;
- (b) removing the source solution from contact with the composition to which the desired amine or amino acid enantiomer has been complexed;
- (c) contacting the composition having the desired amine or amino acid enantiomer complexed thereto with a smaller volume of an aqueous receiving solution in which the desired amine or amino acid enantiomer is soluble, or which has greater affinity for such desired amine or amino acid enantiomer than does the ligand portion of the composition, or which has a greater affinity for the ligand than does the desired amine or amino acid enantiomer, thereby quantitatively stripping such desired amine or amino acid enantiomer from the ligand;
- and
- (d) recovering the desired amine or amino acid enantiomer in concentrated form in the receiving solution.
A nonchromatographic method of separating an enantomeric molecule from its counter-enantiomer comprising:
- (a) flowing a feed solution containing a desired enantiomer and its counter-enantiomer through a separation device having a ligand bound to a solid support wherein the ligand has an affinity for the desired enantiomer and a selectivity of at least 4;
- (b) selectively forming a complex between the desired enantiomer and the ligand thereby forming a first raffinate having increased purity of the counter-enantiomer;
- (c) breaking the complex between the desired enantiomer and the ligand with a smaller volume of an aqueous receiving solution in which the desired enantiomer is soluble, or which has greater affinity for such desired enantiomer than does the ligand portion of the composition, or which has a greater affinity for the ligand than does the desired enantiomer, thereby quantitatively stripping such desired enantiomer from the ligand and forming a desired enantiomer enhanced receiving liquid;
- (d) flowing the desired enantiomer enhanced receiving liquid through a separation device having ligands bound to solid supports wherein the ligand has reverse optical activity as compared to the ligand in step (a) such that the ligand has an affinity for the counter-enantiomer;
- and
- (e) selectively forming a complex between the counter-enantiomer and the ligand thereby forming a second raffinate having increased purity of the desired enantiomer.
Dependencies are inferred from the claim text.