Aza-Bodipy/DOX Loaded Mesoporous Silicon Nanoparticles And Its Application In Photothermal Therapy And Controlled Drug Release

Cancer has become one of the deadliest killers of the 21st century.The rapid development of nanotechnology has brought new hope to cancer treatment.Among the many nano-reagents used in cancer treatment,mesoporous silicon nanomaterials are the most widely used.Mesoporous silicon-based materials have advantages such as easy surface function,high specific surface area,large pore volume,excellent biocompatibility and biodegradability.Thus,they have been widely used in biomedical fields such as photothermal therapy,photodynamic therapy,tumor imaging,and controlled drug release.In this thesis,two types of mesoporous silica-based nanoparticles have been synthesized and loaded with the organic near-infrared dye Aza-Bodipy and the anticancer drug DOX to explore its application in photothermal therapy and controlled drug release respectively.The main contents include:?1?The C₇₀Si nanoparticles with fullerene as the core and mesoporous silica nanoparticles?MSNs?as the shell layer are synthesized by sol-gel method.Due to the?-?stacking between fullerenes and organic molecules and mesoporous adsorption,the near-infrared dye Aza-Bodipy is successfully loaded by physical adsorption method to obtained C₇₀Si@Bodipy with good water solubility.C₇₀Si nanoparticles endow the near-infrared dye Aza-Bodipy with good water solubility and photostability and solve limitation of hydrophobic Aza-Bodipy in biological application.The experimental results indicate that C₇₀Si@Bodipy nanoparticles showed good photothermal effect in the near-infrared region,and the photothermal conversion efficiency is as high as 34.5%,making the nanoparticles can be applied to photothermal treatments of cells.The results of cell experiments show that the C₇₀Si@Bodipy nanoparticles themselves have low dark cytotoxicity,the material can generate high heat to kill cancer cells under 808 nm laser irradiation.The above results can be concluded that C₇₀Si@Bodipy nanoparticles have the potential for photothermal therapy in vivo.?2?Mesoporous organosilicon nanoparticles?MONs?with-S-S-bonded thioether bridge are successfully synthesized by using the silicon source 1,2-bis?triethoxysilyl?ethane?BTSE?,1,4-bis?triethoxymethylsilyl?propane tetrasulfide?TETS?,and tetraethyl orthosilicate?TEOS?,and the cetyltriethylammnonium bromide?CTAB?as a template under basic conditions.MONs is hydrothermally etched into a yolk-shell structure at 150°C,and the MONs-YS nanoparticles are obtained after removing the CTAB template.The anti-cancer drug DOX are successfully loaded into MONs-YS nanoparticles.The experimental results in aqueous solution and cells indicate that the MONs-YS@DOX release system has the drug release behavior of the tumor microenvironment?GSH?response,and its nanostructure will be degraded accordingly.This kind of biodegradable drug delivery nanosystem is expect to be applied in clinical research.