Study On The Preparation And Performance Of Porous Nanomaterials For Drug Release Of DOX/5-FU And Degradation Of Tetracycline

Objective:Porous nanomaterials assembled with layered double hydroxides(LDHs)are deeply studied in the field of the release of small molecular drugs.Metalloporphyrin modified porous cages of titanium dioxide(TiO2)are used for photodegradation of pharmaceutical pollutantsMethods:1.In this dissertation,a simple liquid-phase synthetic method for the preparation of LDHs is developed.LDHs assembled with nanosheets are proudced by a transformation strategy of zeolitic imidazolate framework-8(ZIF-8)induced by metal Co2+ ions,and the hierarchical porous core-shell structures of LDHs coated ZIF-8(ZIF-8@LDHs)are formed at low temperature,and the porous cages assembled with LDHs nanosheets was obtained at relatively high temperature.2.Using the above two materials as carriers,the performance of loading and release of both LDHs-based porous carriers towards small molecular drugs(DOX:doxorubicin hydrochloride;5-FU:5-fluorouracil)is studied and,the effects of pH and temperature on the release performance are further identified.3.The porous cages of TiO2 are successfully prepared by an amino acid-assisted solvothermal method and a subsequent high-temperature heat treatment process.Afterwards,copper porphyrin(Cu-TCPP),a transition metal complex,is introduced into porous cages of TiO2 by a self-assembly strategy to form a high-performance composite photocatalyst of Cu-TCPP loaded porous cages of TiO2(PC-TiO2-d/Cu-TCPP).4.Tetracycline is degraded under visible light and simulated sunlight,and the performance of various TiO2 materials in photodegradation of pharmaceutical pollutants in the environment was compared along with its influencing factors.Based on this,an enhanced photocatalytic degradation mechanism was explored.Results:1.The hierarchical porous core-shell structure was successfully fabricated by coating ZIF-8 with LDHs,while the porous cage was formed through the assembly of LDHs nanosheets.2.The porous cage assembled by LDHs nanosheets exhibits superior drug release performance compared to the ZIF-8@LDHs hierarchical porous core-shell structure under varying pH and temperature conditions.3.A high-performance composite photocatalyst PC-TiO2-d/Cu-TCPP was successfully synthesized via the self-assembly of a transition metal complex Cu-TCPP and semiconductor TiO2 within porous cages.4.Under visible light or simulated sunlight irradiation,the degradation efficiency of tetracycline by PC-TiO2-d/Cu-TCPP reaches 73.7%and 95.4%,respectively within 100 minutes.Conclusions:1.The hierarchical porous core-shell structure of ZIF-8@LDHs and the porous cage structure assembled by LDHs nanosheets were successfully prepared.2.The LDHs-based porous nano-cage carrier exhibits a favorable drug release profile for DOX.3.The photodegradation of tetracycline is more efficient in a composite structure consisting of PC-TiO2-d/Cu-TCPP porous cages.4.The composite structure of PC-TiO2-d/Cu-TCPP porous cage exhibits superior photodegradation performance towards tetracycline.