Amino And Azobenzene Modified MSiO₂ And Research On Drug Sustained Release Performance

Mesoporous silica has the characteristics of large specific surface area and pore volume,adjustable pore size,biocompatibility and low toxicity.It can be used as an excellent drug carrier.In addition,the surface contains plentiful of silanol which can be modified by functional groups to realize targeted drug delivery at the diseased site and reduce the toxic and side effects to other tissues.Therefore,it is of great significance to prepare functionalized mesoporous silica to realize the controllable release of pharmaceutical environmental stimuli.In this paper,the introduction of amino groups and azobenzene groups into the mesoporous silica improves the controlled release performance of the silica and enables the controlled release of the drug to by UV-light.The specific content is as follows:（1）Mesoporous silica with amino groups was prepared by the sol-gel method using CTAB as template,and amino-containing mesoporous silica modified with azobenzene was prepared by modifying the mesoporous channels or the outer surface respectively.IBU was used as a simulated drug to study the controlled release performance of mesoporous silica.The results show that the samples with azobenzene modified on the outer surface have obvious controlled release performance under ultraviolet light stimulation as the azophenyl group is converted from the trans to cis conformation under the irradiation of ultraviolet light,opening the gates of the pores and releasing the IBU.（2）In order to realize the long-time control release,a mesoporous silica isolation layer was introduced between the amino and azobenzene groups layer of mesoporous silica.The mesoporous silica（Si O₂-NH₂@Si O₂@TSUA）with the inner layer of amino group,the middle layer of hydroxyl group,and the outer layer of azophenyl group（mSiO₂-NH₂@mSiO₂@TSUA）was prepared.IBU is used as a simulated drug to study the controlled release performance of the carrier,but the introduction of the intermediate isolation layer of the carrier does not show obvious contribution to the release.（3）SDS was used as an anionic template to control the distribution of amino groups in the inner core,and mesoporous silica（mSiO₂-NH₂）with uniformly dispersed amino groups was prepared,and then the outer surface is modified by azobenzene groups.To study the controlled release performance of the carrier to IBU,mSiO₂-NH₂@TSUA with mSiO₂-NH₂ to TSUA being3:2 can release 0.55 mg of drug release under ultraviolet light.The carrier drug load and release amount are significantly increased.