EGCG分子印迹壳聚糖膜的制备及性能研究

Preparation and Characterization of EGCG Molecularly Imprinted Chitosan Membrane

利用分子印迹技术,以壳聚糖为功能基体,表没食子儿茶素没食子酸酯(EGCG)为模板分子,硫酸为交联剂,制备了EGCG分子印迹壳聚糖膜,并探讨了平衡吸附时间、pH值、温度及功能单体和模板分子的比例等因素对印迹膜吸附性能的影响.SEM和AFM测试结果表明印迹膜的表面形貌不同于非印迹膜;同时用红外光谱分析了印迹分子的洗脱情况.平衡结合法实验结果表明,印迹膜对EGCG具有较好的亲和性和选择性.Scatchard分析表明,印迹膜在识别EGCG的过程中存在1类结合位点,其平衡结合常数K为4.046,最大吸附量Qmax为49.52mg·g-1.

Molecularly imprinted technology （MIT） is a powerful technique for the preparation of special template molecules that can recognize selectively a specific chemical species. It is widely used in chromatography, solid phase extraction, membrane separation and sensor technology. However, molecularly imprinted membrane is the combination of MIT and membrane technology, which contains not only specific recognition but also mem-brane separation. The main objective of this work is the preparation of epigallocatechin gal- late （EGCG） molecularly imprinted membranes, using chitosan （CS） as functional monomer, EGCG as template, and sulfuric acid as crosslinking agent. The factors such as adsorption time, pH, temperature, and the ratio of functional monomer to template on the adsorption of imprinted membrane were discussed. The surface morphology and structure were observed by SEM and AFM. FTIR characterization confirmed that the imprinting molecule was fully eluted. According to Scatchard analysis, the results show that the water phase of the preparation of molecularly imprinted membrane for the template EGCG has very good recognition ability and selectivity. According the analysis of Scatchard, the result show that the imprinted membrane exist one binding site to EGCG, and the max adsorption capaci-ty of imprinted membrane and equilibrium binding constant arrive at 49.52 mg · g^-1 4. 046, respectively.