Biocompósitos de xSiO2.(y-n)CaO.zP2O5.nCuO/PVA obtidos por tape casting aquoso: propriedades osteogênica e antibacteriana

• Ano de defesa: 2021
• Autor(a) principal: Santos, Silmara Caldas
• Orientador(a): Santos, Euler Araujo dos
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Programa de Pós-Graduação: Pós-Graduação em Ciência e Engenharia de Materiais
• Palavras-chave em Português: Ciência dos materiais; Nanocompósitos (Materiais); Álcool; Vidros bioativos; Bactericidas; Biocompósitos; Poli(álcool vinílico) (PVA); Vidro bioativo; Cobre; Atividade osteogênica; Antibacteriano; Biocomposites
• Palavras-chave em Inglês: Poly(vinyl alcohol) (PVA); Bioglass; Copper; Osteoblast behavior; Antibacterial activity
• Área do conhecimento CNPq: ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA
• Link de acesso: https://ri.ufs.br/jspui/handle/riufs/15078

The guided bone regeneration (GBR) technique is characterized by the use of barrier membranes to close critical bone defects, preventing the invasion of epithelial cells and fibroblasts, complicating actors in the regenerative process. To increase the bioactivity and mechanical properties of materials used as a GBR membrane, some polymer-based biocomposites with bioactive ceramics as filler particles have been developed. Among these, bioactive glass/polymer biocomposites have attracted a lot of attention, since such materials have osteoconductivity. This is due to the presence of bioactive glass, which has the ability to induce the formation of an apatite layer on the surface very similar to the bone mineral phase. The current challenges in the production of biomaterials for GBR are the development of more biocompatible, resorbable and antibacterial systems, since these materials are more exposed to contamination. Thus, the objective of this work was the preparation and characterization of poly(vinyl alcohol) (PVA) polymeric matrix biocomposites and bioactive glass particles containing copper capable of presenting both osteogenic and antibacterial properties, aiming application in GBR. The biocomposites were obtained by aqueous tape casting using PVA as polymer matrix and a bioactive glass obtained by sol-gel composition 60% SiO2 ∙ (36-x)% CaO ∙ 4% P2O5 ∙ x% CuO, where x = 0 , 1 and 3% (mol %). The aqueous tape casting process did not induce significant changes in the composition and structure of bioactive glasses even after 28 h in contact with solvents. The presence of copper decreased the swelling capacity of the biocomposites while inhibiting the increase in degradation in aqueous media over time. Regardless of the copper content, a layer of low crystallinity hydroxyapatite was precipitated on the surface of all samples after immersion in simulated blood plasma (SBF), confirming the bioactivity of the biocomposites. Although there were no evident effects on the adhesion of MG-63 osteoblastic cells, the presence of copper improved cell proliferation and decreased the expression of alkaline phosphatase (ALP) by osteoblasts, compared to samples without copper. Unlike osteoblastic cells, the membranes of Escherichia coli (Gram -) bacteria were clearly damaged by the presence of copper, confirming its antibacterial effect. These results demonstrated that the insertion of bioactive glass containing copper into biocomposites added the antibacterial property so desirable in GBR barrier membranes without compromising the osteogenic properties of the proposed system, which is, therefore, a promising candidate for the GBR technique.