Preparation And Properties Of 10-Hydroxycamptothecin Hybrid Molecular Imprinting Materials

10-Hydroxycamptothecin(HCPT)has attracted widespread attention due to its low toxicity and high anticancer activity.In order to develop a more effective method for the separation and purification of HCPT.In this thesis,two hybrid molecularly imprinted polymers(HMIPs)(AT-HMIPs and MA-HMIPs)and bi-functional monomer hybrid molecularly imprinted polymers(AT/MA-HMIPs)were prepared using two hybrid functional monomers,acrylamide-isocyanate triethoxysilane(AM-TEOSPI)and methacrylic acid-(3-aminopropyl)triethoxysilane(MAA-APTES),respectively,with the aid of computer simulation.Using traditional functional monomers MAA to prepare MAA-MIPs as a control,the recognition and separation properties of four HCPT molecularly imprinted materials were studied.The main research results are as follows:Preparation and characterization of molecular imprinting polymers of HCPT based on hybrid monomers.Firstly,the structure of the template molecule HCPT and nine functional monomers was optimized through computer molecular simulation.The configuration,bond formation,NPA charge distribution,frontier orbital analysis,and binding energy and mechanism of the two prepolymerization systems of HCPT with AM-TEOSPI and MAA-APTES were discussed.The results showed that the binding energy of HCPT to AM-TEOSPI was the lowest(-25.507 kcal/mol),followed by MAA-APTES(-21.963 kcal/mol).At the same time,the interaction between template molecules and functional monomers was verified using Fourier Transform infrared spectroscopy(FTIR)experiments,and the imprinting ratio of template molecules and functional monomers was investigated using ultraviolet spectroscopy.It was found that for HCPT and AM-TEOSPI,MAA-APTES prepolymerization systems,when the imprinting ratio was 1:4,the simulated imprinting effect was the best.Finally,two hybrid molecularly imprinted polymers(AT-HMIPs and MA-HMIPs)were synthesized using the selected two optimal monomers,AM-TEOSPI and MAA-APTES,respectively.They were characterized by FTIR,scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDS)and thermogravimetric analysis(TGA).Preparation and characterization of molecular imprinting of HCPT based on double hybrid monomers.Two hybrid monomers(AM-TEOSPI and MAA-APTES)were simultaneously used as bifunctional monomers.Through computer molecular simulation,the optimal conformation and the lowest binding energy(-46.315 kcal/mol)of the imprinted complex were obtained.Through further analysis,it was found that there were strong hydrogen bonds and van der Waals interactions between the template and the bifunctional monomer in molecular imprinting.Both FTIR and ultraviolet spectroscopy experiments have verified that there is an interaction between the template molecule and the functional monomer,and the optimal imprinting ratio between the template and the bifunctional monomer is 1:4.The bifunctional monomer hybrid molecularly imprinted polymers(AT/MA-HMIPs)of HCPT were synthesized based on the above theoretical and experimental results,and characterized by FTIR,SEM,EDS,mercury intrusion analysis and TGA.Molecular imprinted polymers(MAA-MIPs)were prepared using traditional functional monomers MAA as a comparison.The results show that both polymers have been successfully synthesized.Study on the adsorption performance of HCPT based on bifunctional monomers hybrid molecular imprinting.Four types of molecularly imprinted polymers(AT-HMIPs,MA-HMIPs,AT/MA-HMIPs and MAA-MIPs)were prepared and evaluated for their adsorption properties through isothermal adsorption,kinetic adsorption,thermodynamic adsorption and Scatchard analysis.The adsorption mechanism and behavior of these molecularly imprinted polymers were inspected through adsorption models.The experimental results show that the Langmuir isotherm model and pseudo second order kinetic model agree well with the adsorption results.The maximum adsorption capacity is 18.79 mg/g,and the adsorption equilibrium can be reached within 20 min.In addition,HCPT exhibits excellent selectivity(imprinting factor of10.73)and good recoverability(after 10 adsorption-desorption cycles,the adsorption capacity only decreases by 7.75%).It has good stability within 30 days(adsorption capacity and adsorption efficiency only decreased by 1.09 mg/g and 6.82%).Finally,using AT/MA-HMIPs as a solid phase extraction column filler,and optimizing the conditions of solid phase extraction,a molecular imprinted solid phase extraction column with high selectivity for the separation and enrichment of HCPT from Camptotheca acuminate Decne seeds was prepared.The prepared AT/MA-HMIPs were successfully applied to solid phase extraction columns and the HCPT in Camptotheca acuminate Decne seeds was isolated,and the purity of the purified HCPT was 80.86%,with a yield of 61.43%.The purity of HCPT was 82.39% and the yield was63.74% in leaf extract.The research results have played a guiding role in the efficient separation and purification of HCPT,providing data support for the development of new materials for extracting active ingredients from natural products.