The Growth Of Mesoporous MCM-41Single Crystal And Application In Drug Realease

Mesoporous silica is a kind of new nano-materials which has broad prospects for the development. With the characteristics of ordered mesoscopic structure, narrow an d continuous adjustable pore size distribution within the range of2-50nm, large speci fic surface and abundant unsaturated hydroxyl, it has potential application in separatio n and purification, drug loading and controlled release, information storage, new funct ional materials. Numerous researches indicate that as a drug carrier, mesoporous silica material has good biocompatibility, stability, non-toxic, non-irritating, sustained drug release characteristics. In particular, the structure and morphology of the mesoporous silica can be controlled in nano-micron scale stably. All of the above have attracted wi despread attention result in that a large number of researchers committed to its researc h and exploration.In this thesis, we focus on exploration on morphology control of mesoporous silica, including synthesis of single crystal MCM-41and corresponding impact factors, morphology control using new dual ion surfactant as template and its application in absorption, drug loading. As described below:Exploration for MCM-41single crystal growth. MCM-41single crystal was synthetized using cetyltrimethylammonium bromide (CTAB) and tetraethoxysilane (TEOS) as template and silica source, respectively. Ammonia was used as catalyst. Immobilized semi-batch growth method was applied to control the partical size. The results showed that a crystal form of hexagonal circular bicone of MCM-41crystal with partical size from500to800nm has been observed. With the application of Immobilized semi-batch growth method, the partical size was increased apparently.To determine the dissolution kinetics and thermodynamic properties of mesoporous silica in aqueous ammonia at341K, silicon molybdenum blue spectrophotometry was used. However, tests showed significant difference between and within groups. We believe these were due to the presence of a template CTAB and the designed experiments prove that the silicon element in the solution system can’t combined with ammonium molybdate completely, resulting in instability of the experimental data.Cocondensation synthesis of mesoporous silica in the dilute solution of mixed cationic and aonic surfactants. In this thesis, mesoporous silica with different morphology, such as spherical, vesicle-like, rod-like, spiral fibrous, spiral hexagonal, was synthesized through the condensation of cationic and aonic surfactants in dilute alkaline solution.Based on the exploration of MCM-41single crystal growth, we applied MCM-41with structured morphology and vesicle silica to load drugs. To explore the drug sustained-release effect of mesoporous materials in simulated body fluid.