ZnO NP and PU/ZnO NP composites for controlled delivery of Ibuprofen

• Autor(a) principal: Debelak, Kyle Jacob
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/14483
• topic: Engenharia de materiais; Óxido de zinco; Materiais compósitos; Poliuretanos; Sistemas de administração de fármacos

For the design of drug delivery systems, in which a large amount of drug should be stored and released over a sustained period of time, utilization of nanostructures is frequently advantageous as their high specific surface areas are beneficial for adsorptive drug loading. Additionally, the use of nanostructured drug carriers in concert with polymeric materials in composite drug delivery systems affords control over the drug release characteristics. While many combinations of materials can be imagined, the use of zinc-oxide and poly(urethane) is of particular interest in that nanostructures based on the former are easily producible and the latter is already an established material in biomedical applications. In this investigation, various aspects of the drug delivery properties were examined. In particular, the effects of altering the amount of drug loaded (by loading in solutions of 1, 2, 10, and 20 mg ibuprofen/mL ethanol) were studied and it was demonstrated that the amount of drug loaded can be controlled, which is important for customizing dosages in drug delivery systems. Additionally, the role of a washing procedure after loading the nanoparticles was examined in order to show that these procedures influence the drug loading by removal of loosely bound layers of drug. In completion of this study, the release of ibuprofen from both pure zinc oxide nanoparticles and the composites with poly(urethane) was investigated by tracking the concentration of drug present in a phosphate buffered saline solution containing the drug carrier with respect to time. In order better understand the mechanisms of drug release and analyze the degradation processes of the drug carrier, SEM images were produced for the samples at various times during the drug release process.