Synthesis and characterization of organotriethoxysilanes based on carbohydrates for functional mesoporous organosilica hybrids

• Autor(a) principal: Marta, Andreia Sofia Penedo
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.6/7795
• topic: Biomedical Applications; Carbohydrate Derivative; Mesoporous Hybrids Organosilica; Organotriethoxysilanes; Domínio/Área Científica::Ciências Naturais::Ciências Químicas

Cancer is the second leading cause of death worldwide. Conventional therapies are characterized by clinical inefficiency and serious side effects, like high toxicity in healthy tissues. For these reasons, the investigation for more effective therapies increased in the recent years. With the progress in the area of medicinal chemistry, we read headlines almost every day about potential promising new drugs on the horizon for diseases like cancer, however, these drugs present poor stability, high toxicity, small half-lives, aggregation tendency and the transport is hindered by biobarriers such as the blood brain barrier or cell membranes. To solve these problems, researchers from different areas, such as biology, materials science, pharmacy, medicinal chemistry and chemistry, have oriented their work with the aim to develop more efficient drug delivery systems. In the past decades, the advances of nanotechnology have facilitated the development of several nanovehicles as drug delivery systems, as an advantage in the field of Medicinal Chemistry. Among the nanomaterials proposed, hybrid mesoporous organosilicas have aroused significant interest as candidates for nanomedical applications. The aim of this work was to synthesize mono-organosilanes precursors based on carbohydrates derivatives. The use of carbohydrate as organic part is an innovative work with great potential to prepare anti-tumoral supports for drug delivery, once carbohydrates are involved in numerous important biological processes linked to cancer. In the first part of the present work, was synthesised the carbohydrates derivates, from D-glucose, D-ribose, 1,2:5,6-di-O-isopropylidene-a-D-glucofuranose and methyl-?-D-glucopyranoside. In the second part of the work, was prepared the organotriethoxysilanes involving a cross-link between the carbohydrate derivatives and 3-(triethoxysilyl)propyl isocyanate. Then, these organotriethoxysilanes will be used to functionalized mesoporous hybrids organosilica, with the aim of achieve carrier systems for anti-tumoral drug delivery. The functionalities into the mesoporous materials will interact with potential new drugs or others already in the market, and release them to the specific target sites, giving new and better ways to hit the disease target.