Macroporous silicon-wollastonite scaffold with Sr/Se/Zn/Mg-substituted hydroxyapatite/chitosan hydrogel

Abstract

The scaffolds, which morphologically and physiologically mimic natural features of the bone, are of a high demand for regenerative medicine. To address this challenge, bioactive porous silicon/wollastonite (SC) scaffold has been developed for potential bone tissue engineering applications. Additive manufacturing through the selective laser melting approach has been exploited to fabricate computer-aided designed scaffolds with a pore size of 400 μm. To increase the biocompatibility and osteogenic properties of SC scaffolds, the hydrogel based on a mixture of four mono-substituted hydroxyapatites (sHAp) and biopolymer chitosan (CHT) has been incorporated into SC by impregnation and freeze-gelation method. The pore size of 400 μm of SC has provided enough space for the impregnation of polymer solution and composite (CHT/sHAp) suspension to form highly porous hydrogel within pores. By the combination of SC and CHT/sHAp, both cell attachment and homogeneous proliferation on SC scaffold as well as mechanical properties of CHT/sHAp hydrogel have been improved.

Keywords

• Bone regeneration
• Chitosan
• Hydroxyapatite
• Ion substitution
• Scaffold
• Selective laser melting