Preparation And Evaluation Of Molecularly Imprinted Polymers With Doping Of POSS And MCM-41

Molecular imprinting technology as a kind of emerging technology that can specifically recognize the target molecules,it has become a hot topic in the field of current research.At the same time,organic-inorganic hybrid materials have achieved good development due to their excellent properties and are unique in the field of materials.The combination of organic-inorganic hybrid materials and molecular imprinting techniques can improve the performance of molecularly imprinted polymer（MIP）and extend the use of MIP.For example,polyhedral oligomeric silsesquioxanes（POSS）have a polyhedral cage structure and Mesoporous molecular sieve MCM-41 has a hexagonal symmetrical pore structure and adjustable pore size,both of which have specific structure and properties and have been widely used.Both POSS and MCM-41 have a large specific surface area,which can increase the imprinted sites and enhances the specific recognition of template molecules on MIPs,which makes it possible to use them as solid-phase extraction adsorbents and drug-loading materials.On the basis of above,POSS and MCM-41-MPS derivatized withγ-MPS are used to prepare the molecularly imprinted monolithic columns,and finally applied to the study of S-NAP solid-phase extraction and drug slow controlled release material.In the first part,ionic liquid（[BMIM]BF₄）and dimethylsulfoxide（DMSO）were used as binary porogen,4-vinylpyridine（4-VP）as functional monomer,S-NAP molecularly imprinted monolithic columns were prepared by co-doping POSS and MCM-41-MPS with EDMA as cross-linker.The molecularly imprinted monolithic columns were optimized by examining the ratio of S-NAP to 4-VP,the ratio of[BMIM]BF₄ to DMSO in the binary porogen,the content of POSS and the content of MCM-41-MPS.The results showed that POSS&MCM-41-MPS MIP has specific recognition effect on template molecule S-NAP with the imprinting factor of 6.86.Frontal chromatography was analyzed by Langmuir-Freundlich equation.The result showed that POSS&MCM-41-MPS MIP had a larger saturated adsorption capacity and binding sites than MIP,which were 3.2 mg/g and 13.9μmol/g,respectively.The result of solid-phase extraction showed that the maximum recovery was 97.65%and the value of relative standard deviation（RSD）was 0.94%at the concentration of 0.5μg/mL,the value of limit of detection（LOD）and limit of quantitation（LOQ）were1.21×10^-5 g/L and 4.04×10^-55 g/L,respectively.In conclusion,hybrid materials POSS and MCM-41-MPS can significantly improve the imprinting effect and adsorption performance of MIP,which can be applied to solid phase extraction.In the second part,Capecitabine（CAP）was template,acrylamide（AAm）and2-acrylamido-2-methylpropanesulfonic acid（AMPS）as functional monomers,[BMIM]BF₄ and DMSO as binary porogen and EDMA as cross-linker to prepare CAP molecularly imprinted polymers by co-doping POSS and MCM-41-MPS.By examining the ratio of the template/functional monomer and the ratio of the functional monomer and the crosslinking agent,the optimal imprinted monolith column was obtained with the imprinting factor 6.128.In vitro and in vivo pharmacokinetic studies in rats both showed that POSS&MCM-41-MPS MIP was used as the drug loading material,the peak time（4 hours for POSS&MCM-41-MPS MIP and 2 hours for MIP）and relative bioavailability（173.4%for POSS&MCM-41-MPS MIP and 72.5%for MIP）were significantly better than those for MIP without POSS and MCM-41-MPS.Therefore,the molecularly imprinted polymer POSS&MCM-41-MPS MIP is expected to serve as a drug controlled release carrier.