【作者】 马秀玲；

【导师】 陈震；

【作者基本信息】 福建师范大学 ， 高分子化学与物理， 2011， 博士

【摘要】 本论文的研究工作主要以黄酮类物质—柚皮苷(NG)为印迹分子,研究了柚皮苷分子在水相中的印迹识别。首先,利用天然高分子壳聚糖(CS)作为功能体,PEG为致孔剂,制备了柚皮苷分子印迹壳聚糖膜。分别讨论了交联剂、致孔剂和印迹分子的用量对印迹膜结构和性能的影响。用扫描电镜(SEM)、紫外吸收光谱(UV)、红外光谱(FT-IR)进行测试分析。膜的渗透实验结果表明：该印迹膜可有效地在水相中识别印迹分子。同时,将CS负载到二氧化硅(CS@SiO2)上,制成NG印迹CS@SiO2,用X射线粉末衍射(XRD)、FT-IR、SEM等测试技术对该印迹聚合物进行分析表征,探讨了印迹CS@SiO2对印迹分子NG的吸附特性。Scatchard分析表明,该印迹CS@SiO2在识别NG过程中存在1类结合位点。其次,以p-环糊精(p-CD)为功能体,采用两种交联剂(环氧氯丙烷和六亚甲基二异氰酸酯),制备了对NG具有特定识别能力的不同形貌的吸附材料。用SEM、比表面分析仪、FT-IR及核磁共振谱(NMR)进行分析测试。采用平衡吸附实验方法研究了聚合物的吸附性能和选择性能。实验结果表明,棒状印迹聚合物(采用乳液聚合,交联剂为六亚甲基二异氰酸酯)对NG具有较高的亲和性和选择性,印迹因子α为1.53。Scatchard分析表明,棒状印迹聚合物在识别NG过程中存在2类结合位点。再次,以聚乙烯醇缩丁醛(PVB)为基体、p-CD为功能体、NG为印迹分子、交联剂为六亚甲基二异氰酸酯(HMDI),采用分子印迹技术与电纺丝技术相结合,制备NG分子印迹p-CD类纳米纤维。通过SEM、XRD、FT-IR、TG等对印迹纤维进行表征。该印迹纤维具有较好的选择性,经过六次再生实验,吸附性能几乎不变。利用固体致孔剂SiO2对该印迹纤维进行改性,印迹纤维吸附性能有较大的提高。最后,以邻氨基酚为单体,无电活性物质NG为模板分子,用循环伏安法在碳电极上电聚合成能识别NG的敏感膜。通过SEM、XRR及电化学方法对该印迹传感器进行表征,结果表明：印迹传感器敏感膜与非印迹膜在形貌结构和电化学特性方面有明显的不同。此传感器对NG有较好的选择性,响应快(30s),重现性好(RSD=1.79%)。传感器对NG的响应在6.0×10-5～1.4×10-4 mol/L范围内呈线性关系,检出限为1.6×10-5 mol/L。更多还原

【Abstract】 This thesis is mainly the studies on molecular imprinting technique of naringin (NG) in aqueous media.Firstly, a molecularly imprinted membrane (MIM) was prepared in aqueous media using natural biopolymer chitosan (CS) as a functional polymer, NG as a template molecule by phase-inversion technique. The effects of linkage reagent, porogen and imprinting molecule on membranes structure and properties were discussed. The morphologies of the MIM before and after modification with the PEG porogen were observed by scanning electron microscopy (SEM). The infrared spectra (FT-IR) confirmed that the formation of hydrogen bond between functional polymer and template molecules. The NG-CS MIM showed an excellent performance when imprinted membrane was used to separate NG from neohesperidin/naringin in the aqueous media. Meanwhile, a naringin imprinting CS@SiO2 was prepared by using chitosan covering on silicon dioxide as a functional polymer, and characterized with X-ray diffraction (XRD)、FT-IR、SEM and so on. The binding properties were discussed by equilibrium binding experiment method. Scatchard analysis of the imprinted CS@SiO2 suggests that there was a class of binding sites during the molecularly imprinted polymer (MIP) recognizing NG.Secondly, based on two cross linker (hexamethylene diisocyanate, HMDI /epichlorohydrin), different non-covalent NG-β-CD imprinted polymers were prepared by usingβ-cyclodextrine (β-CD) as a functional monomer and naringin (NG) as a template molecule, and characterized by means of SEM, BET adsorption apparatus, FT-IR and 1H-nuclear magnetic resonance (1H-NMR). The binding property and selectivity were evaluated by equilibrium binding experiment method. The binding experiments demonstrated that rod-like MIP which was prepared by emulsion polymerization using HMDI as cross linker exhibited the highest selectivity, its imprinting factorsαis 1.53. Scatchard analysis of the rod-like MIP suggests that there were two classes of binding sites during the MIP recognizing NG.Thirdly, a novel molecularly imprinted composite nanofiber was prepared by a simple electrospinning technique, in which PVB was chosen as matrix,β-CD was used as functional monomer and NG as template molecules. After cross-linked by HMDI, the composite nanofiber exhibited a high specific binding capacity. The morphological structure of the nanofibers was studied by means of FT-IR, XRD and SEM. The binding experiments demonstrated that the molecularly imprinted composite nanofiber shows the specific binding sites and the selective binding ability for NG. The molecularly imprinted nanofiber could be used at least six times without any loss in binding capacity. Using silica as the pore-forming reagen, the imprinted nanofiber showed more excellent binding ability for NG.Last, the sensor of NG, a non-electroactive substance, was the first to be prepared based on the molecular imprinting technique. The NG imprinting sensitive film was coated through the electropolymerization of o-aminophenol on the surface of a graphite electrode in the presence of NG which was considered as the template, and characterized by SEM, XRR and electrochemical analyses. The results showed that the imprinted electrode was significantly different from the non-imprinted electrode in morphologies and electrochemical properties, and a linear relationship between the decrease of peak current and the naringin concentration was found in the range of 6.0×10-5-1.4×10-4 mol/L with a detection limit of 1.6×10-5 mol/L. Moreover, the imprinted electrode exhibits a good selectivity and rapid response to the NG template molecules, as well as an excellent reproducibility (RSD=1.79%).更多还原