Preparation,Evaluation,and Application Of Several Kinds Of Magnetic Molecularly Imprinted Particles

Magnetic molecular imprinting technology?MMIT?is a novel type of separation technique with strong magnetic response,high efficient separation and molecular recognition.In this study,the magnetic molecularly imprinted polymers?MMIP?were prepared by combining with molecular imprinting technology?MIT?and magnetic seperation technology for separating and enriching the characteristic components of the natural pharmaceutical active ingredients.It has the advantage of strong magnetic,high recognition,large specific surface area and so forth.This paper studies the preparation and application of three kinds of magnetic imprinted particles.Firstly,we use neomangiferin as template and modified Fe₃O₄ as magnetic carrier to prepare covalently bound molecularly imprinted polymers,explore the optimum conditions of magnetic imprinted polymers,investigate static adsorption properties and selective adsorption capacity,and apply the separation and analysis of natural pharmaceutical active ingredients.The results show:the neomangiferin adsorption capacity of the MMIP reach 1.92 mg/g,is 7.38 times the amount of adsorption Mangiferin.It applied to the analysis of neomangiferin in natural medicine crude extract of Anemarrhena asphodeloides Bunge,sample purity increased from 5.82%to 77.2%.Secondly,four kinds of magnetic molecularly imprinted microspheres were prepared,we choose the best adsorption properties of magnetic imprinted polymers?MCTS-A?.We explored the adsorption mode and mechanism of magnetic imprinted polymer and studied adsorption kinetics,thermodynamics.Magnetic imprinted polymers applied to the analysis of natural medicine and complex samples.The results show:the maximum equilibrium adsorption capacity which MCTS-A to soy isoflavones is 4.95 mg/g.The process is in line with the Langmuir adsorption model and the second-order kinetic model.When used in the analysis and enrichment of xanthene ketones,sample purity increased from 7.94%to 84.2%.When used in the analysis and detection of soymilk,it has the obvious selectivity and enrichment to isoflavones.Finally,we optimized the immobilization conditions of?-amylase with the modified magnetic carrier,investigated the enzymatic properties,storage stability,organic solvents tolerance and recycling rate of the immobilized?-amylase.The results show:the buffer pH of 5.5,reaction temperature of 40?,enzyme concentration of 20 mg/mL,reaction time of 36h are the optimal immobilized reaction conditions.Enzymatic properties of magnetic particles immobilization?-Amylase?MPIA?:the optimum pH 6.5,the optimum temperature 60?.Within 30 days Magnetic Particles Immobilization?-Amylase still maintain 86%of the enzyme activity.MPIA is more stable in non-polar or low-polar solvent.There is 78%of the enzyme vitality after recycling six times.Due to natural medicine has the disadvantage of low content of active ingredient,ingredient complex and difficult to enrichment,similar compounds,etc.,the demand of developing a new,efficient and rapid separation method is gradual increasing.Several new magnetic imprinted polymer prepared in this experiment could be a new method for the analysis of natural pharmaceutical active ingredients,providing a new way for the separation of the active ingredients in natural medicine.