| 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%).
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