Composite scaffolds for bone regeneration and infection control

To overcome the autologous bone graft limitations, tissue engineering is being explored aiming to develop bone substitutes for reconstructions. Our hypothesis is to develop a composite polylactide (PDLLA) scaffold, coated with collagen, containing Bioglass (BG) and minocycline (MH) – an antibiotic with anti-inflammatory and osteoinductive effects - that would be able to provide an improved regeneration with antimicrobial protection. PDLLA scaffolds were prepared by solvent casting/particulate leaching technique and loaded with MH by adsorption. The morphological characterization was performed by SEM as well as the elemental chemical composition (EDS). Crystalline structure was identified by X-ray diffraction (XRD) and attenuated total reflectance (ATR-FTIR) analysis was assessed to identify the functional groups. Antimicrobial activity against Staphylococcus aureus was evaluated by agar diffusion and the biofilm inhibition formation was observed by SEM analysis. Cellular proliferation and activity were evaluated using human osteoblasts (MG-63 cells). SEM images showed the PDLLA surface with interconnected porous; EDS showed that the BG particles were incorporated into the scaffolds; XRD and ATR evidenced chemical interactions between MH and PDLLA; MH-scaffolds presented antimicrobial activity including biofilm formation reduction. Effects on the cellular proliferation and activity were observed on both samples, without important differences. Overall, results show that PDLLA composite scaffolds show potential as antimicrobial and osteoconductive bone grafts.