ABSTRACT
Objective: To prepare quercetin molecularly imprinted polymers (MIPs) by molecular imprinting technique. Methods: This experiment used quercetin as template molecule, acrylamide (AM) as functional monomers, ethylene glycol dimethacrylate (EGDMA) as cross linking agent, and azodiisobutyronitrile (AIBN) as initiator. Using anhydrous ethanol and tetrahydrofuran as pore forming agent, quercetin MIPs were prepared by precipitation polymerization and mass polymerization methods; The optimal proportion between template and functional monomer was chosen by UV and IR; The microstructure of MIPs was investigated by SEM. The adsorption equilibrium time and maximum adsorption of MIPs prepared with two methods were investigated by balance and isothermal adsorption experiment, and the specific adsorption capacity was studied. Results: The experimental research showed that precipitation polymerization method of quercetin MIPs had uniform rules of globular structures. The adsorption kinetics and isothermal adsorption experiment found faster adsorption rate and larger adsorption capacity. Polymer on quercetin had high specificity recognition ability in rutin and quercetin adsorption selective process. Conclusion: Precipitation polymerization of MIPs, with strong selective adsorption, separation and enrichment of chemical components in Chinese medicine flavonoids complex, is a new method of research. At the same time, it also provides reference for chemical composition research of other Chinese materia medica.
ABSTRACT
AIM: To prepare polymethacrylate nanospheres and study the mechanism of breviscapine entrapped by polymethacrylate nanospheres. METHODS: Polymethacrylate nanospheres were prepared by microemulsion polymerization with SDS as surfactant, n-butanol as cosurfactant, MAA and BMA as monomer, TRIM as cross-linker and AIBN as initiator. Breviscapine added would be divided into two ways:prior to polymerization (encapsulation) and after polymerization (sorption), respectively. RESULTS: The size of the nanospheres was found to be 50nm by measuring with TEM. The ? potential of the nanospheres was -27.2 mv and it was increased after breviscapine being entrapped. The drug content entrapped in nanospheres was proportional to the drugs amount added in encapsulation method while the drug content in nanospheres was increased step by step in sorption method. CONCLUSION: The polymethacrylate nanospheres prepared by microemulsion polymerization could be applied to encapsulate hydrophobic traditional Chinese medicine extracts.