Preparation Of Amino-modified Drug-carrying Porous Composites And Their Sustained-release Properties

Objective:In this thesis,an amino-modified drug-loaded porous composite material with pH response is designed to control the release of indomethacin drug under specific pH conditions.This paper uses mesoporous silica SBA-16 as Basic structure,a drug nanocarrier with pH response was prepared,and it was loaded with indomethacin,and its release in vitro was studied.During the preparation of the drug carrier,the basic structure modification and encapsulation are completed and characterized.In in vitro release studies,response under specific pH conditions is accomplished.Methods:The dual template-assisted sol-gel method was used to synthesize mesoporous silica SBA-16,and the key process parameters such as the ratio of dual template,reaction temperature,and acidity were investigated.In order to increase the drug loading of mesoporous materials,the structure of SBA-16 was modified,and the best value of indomethacin in different media was investigated.The cross-linked gelatin polymer system was used to wrap the drug-loaded material and its cumulative release in simulated body fluids was studied.FT-IR,UV-vis,X-ray diffraction（XRD）,thermogravimetric analysis（TGA）,scanning electron microscope（SEM）,transmission electron microscope（TEM）)And nitrogen adsorption-desorption（N₂ adsorption-desorption）to characterize the structure and morphology of drug-loaded composites.Finally,the in vitro simulated release of indomethacin was studied in different media（pH=2,6.8 and 7.4）at 37±1℃.Results:1.The best conditions for the preparation of mesoporous silica SBA-16were obtained through experiments.The template was 0.14 gP123 and 0.74 gF127,t he reaction temperature was 35℃,and the acidic condition was a 1 M hydrochloric acid solution.SBA-16,the template is removed by washing,crystallization and calci nation to obtain pure SBA-16.The best conditions for the preparation of amino-modified mesoporous silica SBA-16were obtained through experiments.The toluene solution was used as the amino-functionalized reaction solvent,ATPES was used as the amination reagent,and the reaction was performed under a nitrogen atmosphere.The obtained solid was washed and dried to obtain NH₂-SBA-16.2.Experiments show that for poorly soluble drugs,the drug load of SBA-16@IMC is 38.71%,and the drug load of NH₂-SBA-16@IMC is 40.1%.Modified mes oporous material.3.When the gelatin solution is 20%,the 50%glutaraldehyde solution is 0.6 ml,and the mass ratio of gelatin to the drug-loading system is 1:1,it has a significant effect on the crosslinking results of gelatin.Among them,the amount of glutaraldehy de is the most affected gelatin crosslinking effect.4.In vitro simulated drug release experiments showed that SBA-16@IMC,NH₂-SBA-16@IMC,SBA-16@IMC@GA,NH₂-SBA-16@IMC@GA four drug carriers in different media（pH=2,6.8 and 7.4）Release at 37±1°C,with a cert ain pH response.Conclusion:A drug carrier was prepared with mesoporous silica SBA-16 as the basic structure,modified with functionalized functional groups,and coated with gela tin after crosslinking.The carrier-loaded drug indomethacin can respond to release un der the pH environment of the colon,providing a reference for the development of t herapeutic materials for colonic sites.