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|Title:||Caracterização fluidodinamica no recobrimento de celulose microcristalina em leito fluidizado|
|Author:||Cunha, Roberto Luis Gomes da|
|Advisor:||Rocha, Sandra Cristina dos Santos, 1957-|
|Abstract:||Resumo: O recobrimento de materiais granulares é urna operação bastante utilizada pela industria Farmacêutica com diversas finalidades, que vão desde fatores estéticos ao controle da taxa de dissolução de substâncias químicas e incluem: facilitar a administração através da obtenção de uma super:ficie lisa, identificar o medicamento pelo emprego de cores, proteger a droga de agentes atmosféricos como, luz, oxigênio, entre outros. Neste trabalho estudou-se a fluido dinâmica e o recobrimento da celulose microcristalina - MICROCEL, que é o principal excipiente usado na indústria farmacêutica, com uma suspensão aquosa a base de Eudragit'1!|
Abstract: The coating of granular materials is an operation widely used by tbe Pharrnaceutical industry with diverse purposes: to improve the product appearance, to obtain a product with controlled release of active components, to facilitate the administration through the artainrnent of a smooth surface, to identii)r the drug by colors, to prateet the drug ITom atmospheric agents as, light, oxygen, among others. ln this work, the fluid dy11aID.ics and the coating of microcrystalline cellulose - MICROCEL, which is the main excipient used in the pharmaceutical industry, was analyzed. An aqueous polymeric suspension of Eudragit@ was used as the coating liquid in a fluidized bed. The suspension was eontinuously sprayed on the granules by a double-fluid nome loeated at the top ofthe bed. The objeetive of this work was to analyze the fluid-dynamics of a fluidized bed during the coating process, using particles of type B according to Geldart classification, aiming at the identillcation of the bed saturation (instability andíor fluidized regime collapse) and relating it to the operating conditions. The independent variables analyzed were the flow rate of eoating suspension (Ws), for the values: 6.4, 11.0 and 18.0 glmin and the atomization pressure (pat) in the following levels: 10, 15 and 20 psig. The inlet aÍ! temperature of the bed was kept constant at 70°C, as well as the sÍZe of the particles, in the range of 0.30 - 0.42 mIn. A 32 factorial desígn was employed to evaluate the influences of the operating condítions on the responses: the process efficíeney, the partíc1es growth, the agglomerate formation and the instantaneous saturation until the bed collapse. The process efficiency varied ITom 51 to 99,7 %, the particles growth was characteristíc of a fi1m coating, the agglomerates índex varied ITom 0.38 to 6.28 % and the bed instantaneous saturation ITom 5.370.10-3 to 16.828.10-3 (min-l). During the experiments, i1 was observed that the fluidized regime collapse is related to the bed saturation, since the bed porosity decreases with the saturation increase, with consequent packing of the particles and collapse ofthe bed regime
|Appears in Collections:||FEQ - Dissertação e Tese|
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