Research On Drug Delivery System Based On Mesoporous Silica

Drug Controlled Release System（DCRS）can achieve targeted release of drugs in specific areas,thereby reducing the toxic and side effects of drugs and improving the efficiency of drug action,so it has a broad application prospect in the field of biomedicine.For an ideal DCRS,the loaded drug is required to achieve zero release before reaching the designated area,and to achieve as much release as possible after reaching the designated area.At present,the research progress of DCRS has not reached the ideal goal,so its exploration still has high research significance.Mesoporous silica nanoparticles（MSNP）is an excellent drug carrier material,which has adjustable morphology,adjustable mesoporous pores,larger specific surface area,larger pore volume,Non-toxic and safe,stable structure,good biocompatibility and easy modification.Because of its good performance,it is widely used in the fields of industrial catalysis,sensors,separation and adsorption,and biomedicine,especially in the preparation of drug carriers and drug development.In this paper,MSNP is used as the basic material to design and synthesize a drug controlled release system with pH and magnetic response.A new type of pH-responsive MSNP/β-CD drug controlled release system with controlled release of febuxostat（Febuxostat,Fbst）was prepared.The system uses MSNP to provide loading space for Fbst drugs and uses iodopropyltrimethoxysilane（IPTES）is surface-modified and coupled with benzimidazole molecules,and then combined with cyclodextrin molecules through supramolecular interactions to block the drug.When the pH value of the environment decreases,the supramolecular nanovalve on MSNP is activated to realize the release of drugs.In the prepared MSNP-SS-CS drug carrier,MSNP provides the required loading space for the Fbst drug.The surface is modified with Aminopropyltriethoxysilane（APTES）by the post-modification method,and then the surface is modified by connecting cysteine.Cystine（Cys）modified the disulfide bonds on the surface of MSNP,and finally,chitosan（CS）was grafted onto the surface of MSNP-SS to block the pores.The system can use glutathione（GSH）to break the disulfide bond,and pH stimulates the dual control response to achieve controlled release of the drug.A new type of nano drug delivery system Fe₃O₄@MSNP/GQDs with magnetic targeting and pH response controlled drug release was synthesized.The low cytotoxicity and good biocompatibility of Fe₃O₄ and MSNP are used to construct core-shell structural materials.The MSNP shell provides the required loading space for the drug,and the paramagnetic Fe₃O₄ core makes the composite material targeted.GQDs can bind to the amino groups modified on the surface of the material,thereby sealing the drug molecules in the pores.When the environmental pH decreases,the bond between the GQDs and the drug-carrying material is broken,and the controlled release of the drug can be achieved.