Mechanical properties and in vitro evaluation of bioactivity and degradation of dexamethasone-releasing poly-d-l-lactide/nano-hydroxyapatite composite scaffolds

• A novel technique has been developed to prepare drug releasing composite scaffolds.
• PDLLA/nano-HAp scaffolds show a better bioactivity than that of PDLLA ones.
• Factors that affect in vitro mechanical properties of the scaffolds have been studied.
• pH-compensation effect has been found in the composite scaffolds.
• These composite scaffolds have high potential for cancellous bone regeneration.

The purpose of this study was to fabricate drug-release nano-composite scaffolds and perform in vitro evaluation of their mechanical properties, bioactivity, biodegradability and drug release behaviors. Porous drug-release poly-d-l-lactide (PDLLA) composite scaffolds filled with different amounts of nano-hydroxyapatite (nano-HAp) were prepared by a technique combining polymer coagulation, cold compression moulding, salt leaching and drug coating. Apatite detected on the scaffolds after exposure to a simulated body fluid showed improvement in bioactivity and the apatite formation ability through the addition of the nano-HAp content in the composites. Nano-HAp incorporation and apatite formation made a positive impact on the mechanical properties of the scaffolds; however, plasticization and degradation of PDLLA had a negative impact. The pH-compensation effect of the composite scaffolds can reduce the risk of chronic inflammation complications. The fabrication method in this study can produce scaffolds with controllable structure, appropriate mechanical properties and degradation rates for cancellous bone repair applications.

Figure optionsDownload high-quality image (210 K)Download as PowerPoint slide