Preparation Of Magnetic Molecularly Imprinted Polymer And Its Application In Protein Separation And Purification

Molecular imprinting is a type of polymer synthesis technology,which is widely used for effective and specific recognition of target molecules.Its principle is gradually deduced based on the theory of interaction between antibody and antigen proposed by L.C.Pauling in the 1940s which can be summarized as a process in which a molecule recognizes another molecule through non-covalent bond or covalent bond interaction.The molecularly imprinted materials prepared by this technology have specific recognition and selective adsorption for template molecules.However,there are still some problems in the preparation process.For macromolecular polymers,such as proteins.it is often difficult to use it as a stable template for synthetic polymers due to the volatile nature of proteins.Moreover,the structure of proteins is unstable and highly susceptible to temperature,ionic environment and pH value.For these reasons,it is difficult to control the influencing factors during the experiment and control the imprinting process of the synthesis reaction.Therefore,researchers are trying to find a new method of western blotting that can break through the bottleneck,overcome these defects of proteins and realize a gentle and efficient extraction method for protein templates in blots.In order to solve the above problems,Fe3O4 magnetic particles were used as carriers to prepare temperature-sensitive magnetic imprinted particles,magnetic responsive molecularly imprinted hydrogels and magnetic responsive molecularly imprinted porous membranes in this paper.The main conclusions are as follows:(1)Temperature-sensitive magnetic imprinted particles Fe3O4@BSA-MIP and non-imprinted temperature-sensitive magnetic particles Fe3O4@NIP were prepared by surface imprinting method.The magnetic properties,group composition,and microstructure were characterized by VSM,FT-IR,TEM;adsorption performance,experimental error and adsorption mechanism were studied by adsorption kinetics,adsorption isotherm,Scatchard,Langmuir,Freundlich;The thermosensitive properties were studied by thermosensitive experiments.The results show that the prepared Fe3O4@BSA-MIP and Fe3O4@NIP are paramagnetic and uniformly dispersed,the adsorption performance of Fe3O4@BSA-MIP is stronger than that of Fe3O4@NIP and Fe3O4@BSA-MIP has the highest adsorption capacity when the template solution was absorbed at 35?.(2)The BSA-imprinted hydrogel with Fe3O4@BSA-MIP(BSA-based molecularly imprinted hydrogel with Fe3O4@BSA-MIP,Fe3O4@BSA-MIP@BSA-MIH)was prepared by UV-initiated polymerization.The microscopic morphology and elemental composition were characterized by SEM,LSM,and XPS.The adsorption performance and specific recognition performance of four different compositions of hydrogels including Fe3O4@BSA-MIP@BSA-MIH were investigated by adsorption kinetics,adsorption isotherm,Scatchard,Lamguir,Freundlich and HPLC.The template elution efficiency of Fe3O4@BSA-MIP@BSA-MIH at 0?80 Gs was investigated by adjusting the magnetic field with Holmhertz coil.The results show that Fe3O4@BSA-MIP@BSA-MIH with double imprinting has the strongest adsorption capacity and the highest efficiency of template elution when the magnetic field is 15 Gs.(3)The BSA-imprinted porous membrane with Fe3O4@BSA-MIP(BSA-based molecularly imprinted membrane with Fe3O4@BSA-MIP,Fe3O4@BSA-MIP@BSA-MIM)was prepared by surface imprinting method.The microscopic morphology and elemental composition were observed by SEM,LSM and XPS;The adsorption properties of four different compositions membranes including Fe3O4@BSA-MIP@BSA-MIM were observed by adsorption kinetics,adsorption isotherms,Scatchard,Lamguir,Freundlich;The elution efficiency of Fe3O4@BSA-MIP@BSA-MIM at 0?80Gs was investigated by adjusting the magnetic field with Holmhertz coil.The results show that the double-imprinted Fe3O4@BSA-MIP@BSA-MIM has the strongest adsorption capacity and has the highest elution efficiency at 15Gs.(4)The adsorption capacity and adsorption mechanism of the above various MIP polymers and NIP polymers were studied.Finally,according to the experimental fitting curve,it was found that the prepared magnetic MIP particles,magnetic responsive MIP hydrogels and magnetic responsive MIP porous membranes generally conform to Freundlich which is multi-molecular interlayer adsorption;NIP magnetic particles,NIP hydrogels and NIP porous membranes generally conform to Langmuir which is adsorption between monolayers.According to the adsorption curve,it was found that the adsorption capacity of MIP polymer was stronger than that of NIP polymer.