Alternative molecularly imprinted membranes from a derivative of natural polymer, cellulose acetate

Molecularly imprinted polymeric membranes were prepared from cellulose acetate (CA), of which acetyl content was 40%, by applying the alternative molecular imprinting technique. The Z-d-Glu imprinted polymeric membranes thus obtained recognized d-Glu in preference to l-Glu from racemic Glu mixtures and vice versa. The affinity constants between Glu and the chiral recognition site for two kinds of membranes were determined to be 3.1 × 103 mol−1 dm3 from the adsorption isotherm of d-Glu or L-Glu in the molecularly imprinted CA membranes. Enantioselective electrodialysis was attained with the present membranes reflecting their adsorption selectivity. d-Glu was preferentially permeated through the Z-d-Glu imprinted CA membrane, whereas L-Glu was permeated through the Z-L-Glu imprinted CA membrane. The present study suggests that the molecularly imprinted CA membranes are applicable to the optical resolution of racemic amino acids.