Journal of Polymer Science Part A: Polymer Chemistry, Vol.43, No.2, 385-396, 2005
Optical resolution of racemic amino acid derivatives with molecularly imprinted membranes bearing oligopeptide tweezers
Molecularly imprinted polymeric membranes were prepared from various oligopeptide tweezers by the adoption of N-alpha-tert-butoxycarbonyl-D-tryptophan (Boc-D-Trp) or N-alpha-tert-butoxycarbonyl-L-tryptophan (Boc-L-Trp) as a print molecule. The chiral recognition ability of the formed molecular recognition sites was dependent on the absolute configuration of the print molecule adopted in the membrane preparation (molecular imprinting) process, whereas the candidate oligopeptide tweezers consisted of the L-amino acid residues. In other words, the membranes imprinted by the D-isomer recognized the D-isomer in preference to the corresponding L-isomer, and vice versa. The affinity constant between the target molecule and the chiral recognition site from the oligopeptide tweezers was higher than that from a single-strand oligopeptide derivative. Those membranes selectively transported the enantiomer, which was preferentially incorporated into the membrane by dialysis. The permselectivities for these membranes exceeded their adsorption selectivities. (C) 2004 Wiley Periodicals, Inc.
Keywords:adsorption selectivity;chiral recognition;dialysis;enantioselective permeation;membranes;molecular imprinting;molecular recognition;oligopeptide tweezers;optical resolution;permselectivity