Controllable Synthesis And Biological Application Of Dendrimer-Like Mesoporous Silicon Materials

Mesoporous silicon nanomaterials have received great attention in nano drug delivery systems in recent years due to their unique structure and physicochemical properties.Compared with traditional porous silica nanoparticles,dendrimer-like nanosilica materials have three-dimensional dendritic skeletons and a large of emitting pore structures,which present a larger specific surface area and a higher loading capacity.Therefore,dendrimer-like nano-silicon materials could become a kind of carrier materials to effectively carry macromolecular proteins,drug molecules,luminescent compounds,and vaccine.Through the adjustment of the preparation conditions,mesoporous nanomaterials with different morphologies,particle sizes,and pore structures could be effectively synthesized,providing experimental support for the application and development of new silicon carrier materials.Therefore,this dissertation focuses on the research of the structural adjustment factors,drug loading capacity,biological imaging and biological applications of the dendrimer-like nanosilica materials.The full text mainly includes the following four parts:Chapter 1: The synthetic methods of mesoporous materials and their applications in biological field such as drug delivery,bioimaging,and bioactive materials as tissue regeneration were briefly introduced.Chapter 2: The synthesis of dendrimer-like mesoporous silicon materials with secondary pore structure and their biocompatibility as drug carriers were studied.The effects of reaction conditions on the synthesis of dendrimer-like mesoporous silicon materials with secondary pore structure were investigated by controlling the content of raw materials,reaction temperature,stirring speed,reaction time and other conditions.The biocompatibility of the materials was explored by experiments of cytotoxicity and in vitro degradation.Finally,the typical dendrimer-like mesoporous silicon materials were further used as an efficient co-delivery nanocarrier for intracellular delivery of DOX and RNase A,which demonstrated that the nanomaterials with hierachical dualpore structure is a promising drug co-delivery nanocarriers.Chapter 3: The synthesis of ruthenium complex-doped dendrimer-like mesoporous silicon materials and their application in bioimaging as drug carriers were investigated.By using ruthenium compound with functional group as raw material,a kind of luminescent ruthenium complex-doped dendrimer-like mesoporous silicon material was first prepared.The cytotoxicity,drug loading capacity and bioimaging application of the material were explored.The results indicated that the cytotoxicity of the ruthenium-doped dendrimer-like mesoporous silicon material was lower compared with the ruthenium complex itself.At the same time,the ruthenium-doped dendrimerlike mesoporous silicon material not only has a certain drug loading capacity,but also has the function of intracellular imaging.Therefore,the luminescent complex-doped dendrimer-like mesoporous silicon material could be used for real-time clinical monitoring and drug delivery.Chapter 4: The synthesis of dendrimer-like organic mesoporous silicon material and its application as vaccine adjuvant were explored.By changing different organosilicon compounds as raw material,the dendrimer-like organic mesoporous silicon materials with ethyl and thioether group were synthesized,respectively,and the synthesis conditions of these materials were investigated in detail.The biocompatibility of the dendrimer-like organic mesoporous silicon material was evaluated by cytotoxicity experiments,hemolysis experiments and in vitro degradation.Furthermore,guinea pigs were used as animal models to explore the application of the organic mesoporous silicon materials in vaccine adjuvant.The results indicated that the dendrimer-like organic mesoporous silicon materials could enhance the immune response of guinea pigs and be basically completely degraded within one month,which provides an experimental data for the application of the organic mesoporous silicon materials in animal immunity.