Navegando por Palavras-chave "Granules"

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    Injetabilidade De Grânulos De β-Tcp E Wollastonita Obtidos Pelo Método De Spray Drying Para Preenchimento De Defeito Ósseo
    (Universidade Federal de São Paulo (UNIFESP), 2017-05-29) Almeida, Gleice Ellen Morais De [UNIFESP]; Motisuke, Mariana [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The need for biomaterials to treat bone defects is growing considerably. Thereby, the importance of studies that seek alternatives to treat bone tissue and postpone the need for more severe surgeries increases every day. To this end, the use of bioceramics, such as calcium silicates (wollastonite - CaSiO3) and β-TCP becomes interesting since they are bioactive and osteoconductive. There are many studies in the literature evaluating the possibility of using these bioceramics for filling bone defects. Therefore, the production of granules with controlled shape and porosity becomes interesting since it may allow cell adhesion, assist bone growth and facilitates the filling of an irregular defect. The granules can be obtained by spray drying, which is a granulation process widely used in industry and, in the last recent years, this process has been used to the manufacture of granules for biomedical applications because it is a versatile process that allows the production in a large scale, with low risk of contamination and high reproducibility. The application of granules for filling bone defects through minimally invasive surgical techniques becomes interesting since its spherical morphology improves the fluidity of the material and, consequently, improves the injectability of the material. The use of minimally invasive surgical techniques allows quick recovery of the paicent due to rapid bone repair and more simple procedures. From this context, the objective of this work is to obtain and characterize wollastonite and β-TCP granules obtained by the spray drying process to be applied in bone defects by means of minimally invasive techniques. It was possible to obtain cohesive granules when using β-TCP and calcium silicate samples with PEG binder. It was possible to obtain spherical granules and with high fluidity when using gelatin as a binder. The mixture of granules and with a sodium alginate solution lead to an injectable paste, which was homogenized by two different mixing methods, amalgamator and glass plate. After mixing, it observed greater presence of intact granules when the paste was mixed in the glass plate. Injectable pastes obtained by calcined granules and a polymer phase with lower viscosity favored the injectability and cohesion of the paste, becoming the best condition analyzed. The calcination of the granules resulted in higher mechanical properties and, consequently, granules integrity after mixing and injection, being the best condition to be used.
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    Physical characterization of multiparticulate systems
    (Univ Sao Paulo, Conjunto Quimicas, 2017) Issa, Michele Georges; de Souza, Natalia Vieira; Duque, Marcelo Dutra [UNIFESP]; Ferraz, Humberto Gomes
    The search for new pharmaceutical dosage forms and different drug delivery systems already used in therapeutics is a global trend, serving as an opportunity to expand the portfolio for the pharmaceutical industry. In this context, multiparticulate systems, such as pellets, granules, and minitablets, represent an attractive alternative, given the range of possibilities they provide. Among the methods used in the production of these systems, we highlight the process of extrusion-spheronization for pellet manufacture, wet granulation and hot-melt extrusion for the obtention of granules, and direct compression for minitablets. Although highly versatile, depending on the technology chosen, many processes and formulation variables can influence the ensuing stages of manufacture, as well as the final product. Therefore, the characterization of these small units is of fundamental importance for achieving batch homogeneity and optimal product performance. Analyses, including particle size distribution, morphology, density, porosity, mechanical strength and disintegration, are example tests used in this characterization. The objective of this review was to address the most widely used tests for the physical evaluation of multiparticulate systems.