Preparation And Evaluation Of The Molecular Imprinting Thermo-Sensitive Nanoparticles And Low Crosslinking Coating Column

Molecular imprinting technique(MIT) refers to a new way to prepare polymers using template molecules which showing high selectivity and recognition ability to template molecules. The polymers prepared by molecular imprinting technique can highly recognize specific molecule structure and functional group, and can suit for structure-activity reservation type, so we can choose different molecules as templates. Molecularly imprintedpolymers(MIPs) can be applied in various fields, especially in preparing of stationary phase and drug delivery system.The first part of the work, thermosensitive imprinting polymers with Acrylamide acid(AAM) and 2-acrylamide-2-methyl propane sulfonic acid(AMPS) as functional monomer, tetramethylethylenediamine(BIS) as cross linker and S-ofloxacin as template molecule are prepared by precipitation polymerization. The equilbrium adsorption experiment shows that the adsorbing capacity of imprinted polymer with thermosensitive monomer present obvious change by change of temperature. The adsorbing capacity at higher temperature significantly larger than the adsorbing capacity at lower temperature. Relativity, the adsorbing capacity of the imprinting polymer without thermosensitive monomer and non-imprinted polymer change relatively little by temperature. When the molar ratio of AAM and AMPS is 6:5, the imprinting polymer can be most sensitive to temperature. The results illustrate that thermosensitive imprinting polymer with thermosensitive functional monomer get good temperature sensitivity and recognition ability to template molecules.The second part of the work, low-crosslinking imprinted polymer coatings usingquinidine(QND) as template monomer, ethylene glycol dimethacrylate(EDMA) as chemical cross linker, 4-methyl phenyl dicyclohexyl ethylene(MPDE) as physical cross linker, methacrylic acid(MAA) as functional monomer and hydroquinidine(HQND) as template moleculesare prepared by in-situ polymerization. The resulted low-crosslinking open-tubular imprinted capillary can be used to separate enantiomers by means of capillary electrochromatography(CEC), and the resolution of enantiomers HQND/HQN(Hydroquinine) separation achieved on hydroquinidine-imprinted capillary is 1.97, the resolution of enantiomers QND/QN(Quinine) separation is 2.01. The hydroquinidine-imprinted capillary presents good recognition ability and high column performance, theory plates are up to 70,302 plates m-1. The results illustrate that the low-crosslinking hydroquinidine-imprinted capillary using template monomer and physical cross linker can enhance the imprinting intensity and recognition ability, thus successfully used to seperate the template and its isomer.