Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, P. R. China.
J Sep Sci. 2019 Dec;42(23):3544-3552. doi: 10.1002/jssc.201900825. Epub 2019 Oct 15.
An S-mandelic acid imprinted chitosan resin was synthesized by cross-linking chitosan with glutaraldehyde in 2% acetic acid solution. S-Mandelic acid imprinted chitosan resin was used to enantioselectively separate racemic mandelic acid in aqueous medium. When keeping the pH of sample solution (100 mM Tris-H PO ) at 3.5 and adsorption time at 40 min, the enantiomer excess of mandelic acid in supernatant was 78.8%. The adsorption capacities of S-mandelic acid imprinted chitosan resin for S- and R-mandelic acid were determined to be 29.5 and 2.03 mg/g, respectively. While the adsorption capacities of non-imprinted cross-linked chitosan for S- and R-mandelic acid were 2.10 and 2.08 mg/g, respectively. The result suggests that the imprinted caves in S-mandelic acid imprinted chitosan resin are highly matched with S-mandelic acid molecule in space structure and spatial arrangement of action sites. Interestingly, the enantiomer excess value of mandelic acid in supernatant after adsorption of racemic mandelic acid by R-mandelic acid imprinted cross-linked chitosan was 25.4%. The higher enantiomer excess value by S-mandelic acid imprinted chitosan resin suggests that the chiral carbons in chitosan and the imprinted caves in S-mandelic acid imprinted chitosan resin combine to play roles for the enantioselectivity of S-mandelic acid imprinted chitosan resin toward S-mandelic acid. Furthermore, the excellent enantioselectivity of S-mandelic acid imprinted chitosan resin toward S-mandelic acid demonstrates that using chiral chitosan as functional monomer to prepare molecularly imprinted polymers has great potential in enantioseparation of chiral pharmaceuticals.
合成了一种 S-扁桃酸印迹壳聚糖树脂，方法是将壳聚糖与戊二醛在 2%乙酸溶液中交联。S-扁桃酸印迹壳聚糖树脂用于在水介质中对外消旋扁桃酸进行对映选择性分离。当保持样品溶液（100 mM Tris-H PO ）的 pH 值为 3.5 和吸附时间为 40 分钟时，上清液中扁桃酸的对映体过量为 78.8%。S-扁桃酸印迹壳聚糖树脂对 S-和 R-扁桃酸的吸附容量分别为 29.5 和 2.03 mg/g。而非印迹交联壳聚糖对 S-和 R-扁桃酸的吸附容量分别为 2.10 和 2.08 mg/g。结果表明，S-扁桃酸印迹壳聚糖树脂中的印迹空穴在空间结构和作用位点的空间排列上与 S-扁桃酸分子高度匹配。有趣的是，吸附外消旋扁桃酸后，R-扁桃酸印迹交联壳聚糖上上清液中扁桃酸的对映体过量值为 25.4%。S-扁桃酸印迹壳聚糖树脂的对映体过量值较高，表明壳聚糖中的手性碳和 S-扁桃酸印迹壳聚糖树脂中的印迹空穴共同作用，赋予了 S-扁桃酸印迹壳聚糖树脂对 S-扁桃酸的对映选择性。此外，S-扁桃酸印迹壳聚糖树脂对 S-扁桃酸具有优异的对映选择性，表明使用手性壳聚糖作为功能单体制备分子印迹聚合物在手性药物的对映体分离中具有巨大潜力。
