LAUSR

An S-mandelic acid (MA) imprinted chitosan resin (SMIC) was synthesized by cross-linking chitosan with glutaraldehyde in 2% acetic acid solution. SMIC was used to enantioselectively separate racemic MA in aqueous medium. When keeping the pH of sample solution (100 mM Tris-H3 PO4 ) at 3.5 and adsorption time at 40 min, the enantiomer excess (ee) of MA in supernatant was 78.8%. The adsorption capacities of SMIC for S- and R-MA were determined to be 29.5 and 2.03 mg g-1 , respectively. While the adsorption capacities of non-imprinted cross-linked chitosan for S- and R-MA were 2.10 and 2.08 mg g-1 , respectively. The result suggests that the imprinted caves in SMIC are highly matched with S-MA molecule in space structure and spatial arrangement of action sites. Interestingly, the ee value of MA in supernatant after adsorption of racemic MA by R-MA imprinted cross-linked chitosan was 25.4%. The higher ee value by SMIC suggests that the chiral carbons in chitosan and the imprinted caves in SMIC combine to play roles for the enantioselectivity of SMIC toward S-MA. Furthermore, the excellent enantioselectivity of SMIC toward S-MA demonstrates that using chiral chitosan as functional monomer to prepare molecularly imprinted polymers has great potential in enantioseparation of chiral pharmaceuticals. This article is protected by copyright. All rights reserved.