Preparation Of Surface Molecular Imprinted Polymers Basing On Different Carriers And Study Of The Recognition Property For The Protein

The molecular imprinting technology (MIT) is a relatively new separationmethod, which imitates the theory of antigen-antibody. It also has the advantages ofstrong specificity and highly stability, as well as reusability. As a result, it has a widerange of applications in separation, sensor and simulated antibodies fields. Resentyears, molecular imprinting technology has a great development. However, whencompared with small molecules, the imprinting of bio-macromolecules particularlyprotein developed relatively slow and immaturely. There are many inherent problemswith the protein hindering the advancement, such as the huge molecular size, flexibleconformation, complex construction and solubility. As molecular imprintingtechnology gradually develops in the fields of life science, environmental science, itsapplication in protein purification and enrichment will be more and more widely.This paper mainly discussed the application of surface molecular imprintingtechnique on protein separation. Three different types of imprinting carriers werechosen to prepare three kinds of molecularly imprinted polymers, which were used torecognize different protein. Then the recognition performance was taken into account.The main contents are as follows:(1) Preparation of molecularly imprinted polymers by cross-linked chitosan andthe research of recognition property for protein. Lysozyme and glutaraldehydecross-linked chitosan were selected as template and carrier respectively to preparemolecularly imprinted polymers via sol-gel progress.Results showed that the MIPexhibited much higher adsorption capacity for Lys than the non-imprinted polymer(NIP), and the imprinted factor was1.86. The equilibrium time and concentrationwere4h and1.2mg/mL. The theoretical maximum adsorption capacity (Qmax) turnedout to be15.89mg/g. The sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) analysis results showed MIP had relatively high adsorption capacity andexcellent selectivity, which made it possible to remove template protein from differentsample solutions. After three adsorption-desorption cycle, MIP still had75.55%of theadsorption capacity compared with the first time.(2) Preparation of bi-functional monomers molecularly imprinted polymers andthe research of recognition property for protein.The study of bi-functional monomersmolecularly imprinted polymers and selectively recognition for the template bovine serum protein. With double bond modified silica gel as the carrier, acrylamide (AAm)and2-acrylamide-2-methyl-1-propanesulfonic acid (AMPS) as functional monomers,the bovine serum molecularly imprinted polymers were prepared. Experimentalresults showed that the introduction of bi-functional monomers imprinting systemcould improve the specific recognition ability to a certain extent. The optimalproportion of AAm to AMPS is five to one. Kinetics and thermodynamics experimentsalso showed that the MIP could reach adsorption equilibrium in a relatively short time(60min), and also had good adsorption capacity for template protein. The equilibriumconcentration and theoretical maximum adsorption capacity were0.6mg/mL and20.59mg/g. Selective experiments further showed that MIP had good selectiverecognition ability for target protein. After three adsorption-desorption cycle, MIPstill had81.25%of the adsorption capacity compared with the first time.(3) Preparation of bi-functional monomers molecularly imprinted polymersbasing on submicron silicon particles and the research of recognition property forprotein. Good dispersivity, well-shaped submicron scale silicon particles (diameter ofabout200nm) were successfully synthesized through the St ber method. Acrylamide(AAm) and2-acrylamide-2-methyl-1-propanesulfonic acid (AMPS) were still used asfunctional monomer to synthesis bovine serum molecularly imprinted polymermicrospheres of "core-shell" type. The result of transmission electron microscopycharacterization could obviously see of the particles size and core-shell structure.Adsorption experiments showed that this kind of imprinting microsphere ofsubmicron size had good selective recognition ability for template protein (imprintedfactor was1.57) and good reuse performance (the utilization rate was75.33%afterthree circulation). Compared with the imprinting system based on silica gel carrier, itcould be faster (within30min) to reach adsorption equilibrium, and the adsorptionquantity increased as well. According to the theory of Langmuir model, the maximumadsorption capacity was23.90mg/g.