Preparation And Adsorption Performance Of Flavonolds Imprinted Polymer Based On The Surface Of Multi-walled Carbon Nanotubes

Flavonoids are widely exist in nature, but their applications are limited by its complex structure, separation and purification of flavonoids from natural plants is very challenging. As typical flavonoids, apigenin and luteolin have high pharmacological activity. The imprinted polymer ungrafted carbon nanotubes shows the phenomenon of deep buried and low adsorption capacity; however, the imprinted polymer grafted carbon nanotubes effectively avoid the phenomenon of sites deep and improve the adsorption of apigenin and luteolin by binding sites dispersed in the polymer surface.Molecular simiulation is a kind of technique, which establishment model based on atomic level and use computer to simulate the structure and behavior of molecules. From the literature reports, molecular imprinting has been widely researched, but is still in the experimental stage. Its preparation and optimization is affected by many factors, and screening imprinted systems also rely on many time-consuming experiments, and lack of corresponding theoretical guidance. But with the development of computer technology, molecular simulation has been applied to molecular imprinting system, which makes the syste m fast and accurate screening possible.The binding energy is calculated by the MS calculation software when apigenin as template, 4-VP, 2-VP, AM, MAA and MMA as functional monomer, finding the best functional monomer 4-VP. The effect of imprinting system was studied, through the five kinds of porogen menthanol, ethanol, acetone, chloroform and tetrahydrofuran. The adsorption mechanism is explained by calculation in the solution of different water content.The multi-walled carbon nanotubes apigenin, luteolin imprinted polymer were synthesized by taking the multi- walled carbon nanotubes as the carrier, and through bulk polymerization method. The adsorption capacity and selectivity were determined through the imprinted polymer synthesized by the functional monomer of 4-VP, AM, MAA and MMA. And choice the best functional monomer AM. At the same time in apigenin imprinted polymer, the imprinting efficiency was studied which effected by five kinds of pore forming agent menthanol, ethanol, acetone, chloroform and tetrahydrofuran.In the experiment, it was determined that the imprinted polymer adsorption kinetics and the equilibrium isotherms. The kinetics rates were modeled using pseudo- first-order and pseudo-second-order kinetic equations. The date was fitted with Langmuir and Freundich models to describe the equilibrium isotherms. The results revealed that the adsorption kinetics fitted well with the pseudo-second-order model and the adsorption equilibrium fit to Langmuir adsorption isotherms. The Langmuir adsorption isotherm equation of apigenin is y = 0.0363x+1.5775,R2=0.9936. The Langmuir adsorption isotherm equation of Luteolin is y = 0.03607x+2.0150,R2=0.9790.The solid phase extraction was filled with imprinted polymers, and the best eluent and elution were choosed. It was well separated that the mixed solution with same concentration of apigenin and luteolin. The extraction apigenin in apigenin solution increased from 0.425% to 90.93%, and the purity of luteolin in peanut shell increased from 2.62% to 91.62%. They have achieved good enrichment effect.