Development of a hydroxyapatite bone tissue engineering scaffold with a trimodal pore structure

Tissue-engineering scaffold-based strategies have suffered from limited cell depth viability when cultured in vitro, with viable cells existing within the outer 250-500 mu m from the fluid-scaffold interface. This is primarily believed to be due to the lack of nutrient delivery into and waste removal from the inner regions of the scaffold construct. Other issues associated with porous scaffolds involve poor seeding efficiencies and limited cell penetration resulting in heterogeneous cellular distributions. This work focuses on the development a novel hydroxyapatite multi-domain porous scaffold architecture (i.e. a scaffold providing a discrete domain for cell occupancy and a separate domain for nutrient delivery) with the specific objectives of embodying in one scaffold the structures required to optimise cell seeding, cell proliferation and migration and potentially to facilitate vascularisation once implanted in vivo. This paper presents the development of the multidomain architecture and preliminary results on cell viability which show a significant improvement in cell viability in the scaffold interiors.