儿茶素活性成分分子印迹聚合物的固相萃取研究

Study on the solid-phase extraction about catechin active constitutent molecularly imprinted polymer

以表没食子儿茶素没食子酸酯(Epigallocatechin-gallate,EGCG)为模板分子,α-甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,在光冷引发条件下合成EGCG分子印迹聚合物,利用该聚合物制成分子印迹固相萃取柱,用于固相萃取茶叶提取物茶多酚,对萃取柱中的清洗液、洗脱剂、上载量等进行了选择。结果表明,在萃取柱上载样品之后,先用V(甲醇)∶V(水)=1∶9溶液进行清洗,再用V(甲醇)∶V(乙酸)=9∶1混合液进行目标分子的洗脱,可以得到比较纯的目标物质EGCG(色谱峰相对峰面积达92.4%),萃取柱在上载样品并进行清洗、洗脱之后,EGCG的回收率达69.3%。分子印迹柱具有较好的稳定性和耐用性能,使用20次后其选择性识别能力仍未降低,但空白印迹柱却没有这样的选择性识别能力。

A molecularly imprinted polymer （MIP） was prepared under solicitation condition with ray and freeze using methacrylic acid as monomer, Epigallocatechin gallete （EGCG） as template molecule and ethylene glycol dimethaeraylate as the cross-linking agent. Solid-phase extraction column was prepared with MIP as solid-phase material and used for extraction of tea polyphenols from green tae, cleaning agent and eluent and uploading quantity were selected. The optimum conditions to the column were as following： the sample was uploaded, and then the column was cleaned up with methanol-water （1：9, V/V） solution. EGCG was eluted with methanol-acetic acid （9：1, V/V） and pure EGCG was obtained （percentage of relative area of chromatographic peak reached 92.4 % ）. The result showed that the EGCG recovery was 69.3%. solid-phase extraction column with MIP as solid-phase material had good stability and durability and its recognition ability didn＇t descend when the EGCG-MIP column was used 20 times. However, blank solid-phase extraction column without MIP was not as good as MIP column.