| As a typical macrocyclic molecule,?-cyclodextrin is a cyclic oligosaccharide produced by amylose under the catalysis of cyclodextrin glucosyltransferase.In the hollow-cylindrical three-dimensional ring structure of the ?-CD,there is a large amount of hydrophilic hydroxyl groups on the outer side of the conical structure;and the due to the shielding effect of the C-H bond,so the inside of the cavity is hydrophobic;therefore the cavity of the ?-CD has special properties of "hydrophobicity of the inner cavity,hydrophilicity of the outer wall".The ?-CD cavity can form inclusion complexes with a series of organic molecules or metal ions.According to the molecular recognition selectivity of host-guest supermolecules,the preparation of functional polymers using ?-CD as a functional monomer is expected to be useful as an extractant for the separation and enrichment of trace components in practical complex samples.Herein,an innovative double-bond modified ?-cyclodextrin is used as a functional monomer in an aqueous environment to prepare a ?-CD hybrid monolithic column material at the tip of a pipette;at the same time,using the Fe3O4 as a carrier,a magnetic ?-CD polymer was obtained by a simple method;?-CD-POSS magnetic polymer with excellent adsorption performance was prepared using POSS as a modifier for the first time.Coupled with high performance liquid chromatography,a metod to extract and detection carbamate pesticides in food was established.The results indicated the method is simple and has high sensitivity and good recovery.The content of this paper mainly includes the following three parts:(1)An acryloyled ?-cyclodextrin-silica hybrid monolithic column was prepared using a newly improved one-pot method based on sol-gel approach in an aqueous-phase condition for the first time.The prepared monolithic column was characterized by scanning electron microscopy,nitrogen adsorption-desorption,thermogravimetric analysis,Fourier transform infrared spectroscopy and used as the adsorbent for the solid phase microextraction(SPME)of carbendazim and carbaryl.After optimization of the SPME conditions,a simple and sensitive SPME-HPLC method for the determination of carbendazim and carbaryl in vegetables was developed.The proposed method provide a convient and effective pretreatment tool for separation and enrichment of carbendazim and carbaryl in vegetables samples.(2)A novel core-shell ?-CD@Fe3O4 magnetic polymer was prepared by dispersion polymerization and the polymer was characterized.The magnetic ?-CD polymer has the molecular recognition ability of cyclodextrin and the paramagnetic property of Fe3O4,is an ideal magnetic extraction medium for extraction of trace components in complex samples.The synthesis conditions of the material and magnetic extraction conditions were optimized,and a MSPE-HPLC quantitative analysis method was established for carbaryl and carbofuran residues in fruit samples.These results The magnetic separation is rapid and the results are satisfactory.(3)In this chapter,a porous Fe3O4@POSS@?-CD magnetic polymers were synthesized combined octavinyl-POSS and acryloyled-?-CD by surface polymerization,and the polymer was characterized.POSS with rigid groups was introduced to the materials to improve the mechanical stability of materials and enhance the adsorption capacity of materials.The magnetic polymers were used as the absorbent for magnetic solid-phrase extraction(MSPE)to extract carbary and carbofuran and showed good adsorption capacity.These results indicated that the MSPE-HPLC method is promising for the determination of carbaryl and carbofuran at trace amounts. |
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