Preparation, Characterization And Adsorption Performance Study Of Tetrahydropalmatine Molecularly Imprinted Polymers Containing Phenanthrene Ring Skeleton

In this paper, MIP containing skeleton of phenanthrene ring were prepared by suspension polymerization, using THP as the template, ethylene glycol maleic rosinate acrylate as crosslinker, and methacrylic acid (MAA) as the functional monomer. The preparation, characterization and adsorption performance of MIP is studied. The main work of this study is shown as follows:The feasibility of molecular imprinting was tested by UV-vis and FT-IR spectroscopy analysis. Tetrahydropalmatine molecularly imprinted polymers had been prepared by suspension polymerization. The optimal polymerization conditions were as follows:the cross linker was ethylene glycol malefic rosinate acrylate, the functional monomer was methacrylic acid, the molar ratio of template:cross linker:monomer was0.1:1:3, the concentration of monomers was1.08mol·L-1, the porogen was15%(v/v) in the organic solvent, the dispersion agent was sodium dodecyl sulfate (SDS), the stirring rate was800r·min-1, the reaction temperature was95℃and the reaction time was1h. The MIP were characterized with FT-IR, scanning electron microscopy (SEM), nitrogen surface area analyzer and Thermo Gravimetric Analyze. The results showed that there are no the template in the MIP, moreover, the MIP were loose, macroporous and sable.Several important factors that influenced adsorption of the imprinted polymer were explored by static binding assay. The binding characteristics and selectivity of the imprinted polymer were also studied. The optimal adsorption conditions were as follows:the size of polymer particles were250-380μm, the time of adsorption equilibrium was4.5h, the frequency of oscillation was150r·min-1, the temperature of adsorption process was30℃.The adsorption rate of the polymers was in coincidence with Langergen quasi-second order kinetics model and the adsorption isotherms of the polymers showed that the sorption quantity of the MIP was much larger than that of the NMIP. The selectivity adsorption showed that the obtained MIP possessed high selectivity towards the template. The MIP was used to concentrate and purify tetrahydropalmatine.The optimal conditions were obtained by studying the desorption of tetrahydropalmatine molecularly imprinted polymers. The results showed that the desorption rate was over90%by using0.1%HCl·C2H5OH to desorp0.5h. After the MIP being used20times, its absorption capability did not become obviously weak. It was proved that the prepared MIP had excellent stability. The polymer microspheres could be used in cycle.