Nowadays, more and more active pharmaceutical ingredients have poor water solubility, which represents an important challenge in drug discovery and development of oral dosage forms. One of the approaches to enhance water solubility and dissolution rate is to make a solid dispersion, in which a drug is incorporated into mesoporous silica material. The aims of this Master thesis was to experimentally evaluate some of the important physio-chemical characteristics of different commercially available mesoporous silica materials, which could help the researchers to decide about the most appropriate excipient to formulate a solid dispersion, and to make a literature review of already published articles, in which these excipients were used to formulate solid dispersions of poorly water-soluble drug. Six different kinds of commercially available SiO2 particles (Aeroperl 200, Parteck SLC 500, Syloid XDP 3050, Syloid XDP 3150, Syloid 244 FP, Syloid AL-1 FP) were evaluated in terms of particle morphology and size, specific surface area, pore volume and size, flowability and water content and affinity. It was seen that these properties vary among different kinds of particles, but the optimal kind to use in solid dispersion is mostly dependant on the purpose of the study and formulation design. Our systematic literature review of two different databases yielded 60 articles which complied with the purpose of our study. It was seen that scientists use many different active pharmaceutical ingredients belonging to various therapeutic groups, which are most often incorporated into SiO2 types with small particles and bigger pores, such as Sylysia 350 and Syloid 244 FP. Furthermore, a lot of different methods are used to produce solid dispersions, with the most common being solvent evaporation methods. In most of the articles, the acquired solid dispersions were in completely or mostly amorphous form, which mostly remained stable at the specific test conditions. Almost every research also reported on improved solubility by formulating a solid dispersion; in some cases, only dissolution rate was enhanced, but many times, the percentage of the dissolved drug was also increased. There were only a few articles dealing with producing a finished dosage form and confirming in vitro measurements with in vivo results. In finished dosage forms, which were most commonly tablets, the drug content was mostly very low due to the poor tabletting properties of pure solid dispersions. In in vivo testing, solid dispersions contributed to improved pharmacokinetic properties of the drug. In future, it would probably be reasonable to conduct more research, where the aim would be to develop a formulation that could someday also find its place in the market.
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