Characterisation of Foamed Porous Alumina Tissue Scaffolds

Abstract

A porous tissue scaffold depends on its ability to provide functional balance between mechanical strength, pore properties and interconnectivity of pores. High porosity levels, typically greater than 90% and pore sizes above 100µm are required for tissue growth and fixation. Alumina is a stable and very strong bioceramic which, when doped with calcium and phosphate ions, can potentially combine bioactivity with high porosity and high strength. Highly porous alumina foams were synthesized through heat induced chemical breakdown of precursor salt solutions. Pore sizes achieved for foamed alumina with moderate mole fractions are generally larger than 100µm. Foamed alumina with mole fractions on the extreme high and low ends shows lower average pore sizes. Compressive strength of synthesized foams falls in the range of 100kPa to 230kPa, significantly higher than porous biodegradable polymer tissue scaffolds. The significance of this work is that scaffolds can be produced with the unique combination of high porosity, high strength and biocompatibility.