RESUMO
Calcium phosphate cement has been widely investigated as a bone graft substitute due to its excellent self-setting ability, biocompatibility, osteoconductivity and moldability. In addition, mesoporous materials have been studied as potential materials for application in medical devices due to their large surface area, which is capable of loading numerous biological molecules, besides being bioactive. In this study, bone ß-TCP-MCPM-based injectable cement with mesoporous silica particles was synthesized and characterized in terms of its mechanical properties, microstructure, porosity, injectability, in vitro bioactivity and degradability; together with toxicity effects in CHO-K1 cell culture. The results showed that the ß-TCP-MCPM cement is bioactive after soaking in simulated body fluid solution, and mesoporous silica particles provided better physicochemical properties compared with silica-free cement. Toxicity assays showed low CHO-K1 cell viability after treatment with more concentrated extracts (200 mg ml-1). However, this behavior did not compromise the reproductive capacity and did not promote significant DNA damage in those cells. In conclusion, the ß-TCP-MCPM cement associated with mesoporous silica might be considered as a potential bone substitute for the repair and regeneration of bone defects.
Assuntos
Cimentos Ósseos/química , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/química , Fosfatos de Cálcio/química , Dióxido de Silício/química , Animais , Líquidos Corporais , Cimentos Ósseos/toxicidade , Células CHO , Ensaio Cometa , Cricetinae , Cricetulus , Dano ao DNA , Injeções , Teste de Materiais , Testes para Micronúcleos , Porosidade , Regeneração , Estresse MecânicoRESUMO
The aim of this work was the preparation of inorganic mesoporous materials from silica, calcium phosphate and a nonionic surfactant and to evaluate the incorporation and release of different concentrations of osteogenic growth peptide (OGP) for application in bone regeneration. The adsorption and release of the labeled peptide with 5,6-carboxyfluorescein (OGP-CF) from the mesoporous matrix was monitored by fluorescence spectroscopy. The specific surface area was 880 and 484 m(2) g(-1) for pure silica (SiO) and silica/apatite (SiCaP), respectively; the area influenced the percentage of incorporation of the peptide. The release of OGP-CF from the materials in simulated body fluid (SBF) was dependent on the composition of the particles, the amount of incorporated peptide and the degradation of the material. The release of 50% of the peptide content occurred at around 4 and 30 h for SiCaP and SiO, respectively. In conclusion, the materials based on SiO and SiCaP showed in vitro bioactivity and degradation; thus, these materials should be considered as alternative biomaterials for bone regeneration.