Evaluation of bioactive glass incorporated poly(caprolactone)-poly(vinyl alcohol) matrix and the effect of BMP-2 modification

Composite materials having mechanical and biological properties similar to those of human bones are needed for bone regeneration and repair. In the present study, composites were made by incorporating bioactive glass (BG) into polycaprolactone (PCL)-polyvinyl alcohol (PVA) (PCLPVA) matrix. Composites with different BG contents of 10, 25 and 50wt% were fabricated by an in-situ blending method. Physicochemical properties measurements found that the composite with 50wt% BG in the PCLPVA organic matrix exhibited the best mechanical properties (compressive strength and compressive young's modulus up to 32.26MPa and 530.91MPa, respectively). We investigated the effects of the BG content on cell adhesion, proliferation and osteogenic activity of UMR-106 cells grown on the scaffolds using in vitro cell culture assay. The composite scaffolds having 25wt% BG showed a significant increase in their cell adhesion capability and a faster cell proliferation. They also exhibited cell adhesion and spreading morphology after only 5days of culturing. For these reasons, we chose to attach the bone morphogenetic protein (BMP)-2 to this composite. The resulting composite (labeled BMP-2-loaded PCLPVABG25) showed significant improvement in the UMR-106 cells adhesion, in the enhancement in osteogenic differentiation and osteoinductivity of this composite.