Evaluation of mechanical properties, biodegradability and bioactivity of forsteritediopside scaffolds coated by polycaprolacton fumarate

One of the significant challenges in bone tissue engineering is the fabrication of highly porous scaffolds with interconnected pores and appropriate mechanical properties. Commonly available synthetic scaffolds are made of ceramic or polymer, but a better combination of properties can be achieved with a composite or multi-component structure. The aim of this study is to produce three-dimensional (forsterite-diopside) porous scaffolds using space holder technique in order to use in bone tissue engineering. Therefore, forsterite and Diopside nanopowders were synthesized via mechanical activation and sol-gel methods, respectively, and then were mixed with various ratios. After addition of sodium chloride as spacer with appropriate weight percentage, the powder mixture was compacted under the uniaxial compression. In order to remove sodium chloride and develop a porous structure, samples were sintered. After determination of the optimal scaffolds in terms of mechanical properties, the scaffolds were coated with 6 wt.% poly caprolactone fumarate solution and their mechanical, physical and biological properties was evaluated. The results showed that the addition of 10 wt.% diopside nanopowder altered the properties of the scaffolds such that compressive strength increased to 4.36 MPa compared to pure forsterite (3.45 MPa). Applying the polymer coating with cross-linked structure on the optimal scaffolds improved the compressive strength by 23%. Based on the results of Archimedes' principle and SEM micrographs, the addition of 10 wt.% diopside had a negligible effect on the porosity but improved the pores morphology. SEM micrographs of scaffolds after soaking in SBF depicted tiny agglomerated bone-like apatite particles. Considering the results obtained, it seems that, the produced scaffolds could be a good candidate for bone tissue engineering applications.