莱克多巴胺表面分子印迹材料的制备、表征及吸附性能

【目的】制备莱克多巴胺硅胶表面分子印迹材料。【方法】以3-（异丁烯酰氧）丙基三甲氧基硅烷为媒介，将聚甲基丙烯酸（PMAA）偶合接枝到硅胶微粒表面，形成接枝微粒PMAA/SiO2；以莱克多巴胺为模板分子，乙二醇二缩水甘油醚（EGDE）为交联剂，对接枝在硅胶表面的PMAA 大分子链进行分子印迹，制备莱克多巴胺表面分子印迹材料（MIP-PMAA/SiO2）。采用扫描电镜观察了分子印迹材料表面，用红外光谱对分子印迹材料的化学结构进行表征。静态法研究分子印迹材料对莱克多巴胺的结合性能与分子识别特性。【结果】莱克多巴胺分子印迹材料对莱克多巴胺的吸附能力明显强于克仑特罗和沙丁胺醇，吸附量为11.08 mg•g-1，特异性吸附容量为9.93 mg•g-1，印迹指数为9.63，吸附平衡时间为10 min，洗脱5 min，解吸附率为92.3%。【结论】分子印迹材料对莱克多巴胺具有特异的识别选择性、优良的结合亲和性及洗脱性。

Preparation and Characterization of Ractopamine-Imprinted Material Using Surface-Molecular Imprinting Method and Its Adsorption Characteristics

【Objective】 The objective of this experiment is to prepare a molecule-imprinted material on surface of silica gel for ractopamine. 【Method】 Polymethylacrylic acid (PMAA) was grafted onto the surface of silica gel particles via the coupling effect of γ-methacryloxypropyl trimethoxy silane, and the grafting particle PMAA/SiO2 was prepared. Then, the molecular imprinting towards the grafted PMAA was performed with ractopamine as template molecule and ethylene glycol diglycidylether (EGDE) as crosslinking agent by using the surface-molecular imprinting technique established, and the ractopamine molecule- imprinted material MIP-PMAA/SiO2 was prepared. The morphology of MIP-PMAA/SiO2 was observed by SEM，and the chemical structure of MIP-PMAA/SiO2 was characterized by FT-IR. Static method was adopted to study the binding properties and molecule recognition characters of MIP-PMAA/SiO2 for ractopamine.【Result】The MIP-PMAA/SiO2 on the adsorption ability of ractopamine was significantly better than clenbuterol and salbutamol. The adsorption capacity of the MIP-PMAA/SiO2 was 11.08 mg•g-1, the specificity binding capacity was 9.93 mg•g-1, and the imprinted factor of the polymer was 9.63. The adsorption reaction reached equilibrium after 10 min, and the desorption ration of ractopamine reached 92.3% in 5 min.【Conclusion】The experimental results show that MIP-PMAA/SiO2 have specific recognition selectivity, excellent binding affinity and elution property for ractopamine.