Digital light processing bio-scaffolds of hydroxyapatite ceramic foams with multi-level pores using Pickering emulsions as the feedstock

Abstract

To prepare bio-scaffolds with multi-stage pores, excellent mechanical and biological properties to meet the requirements of personalized bone repair, digital light processing using Pickering emulsion as paste has been proposed here firstly for porous hydroxyapatite scaffolds with complex shape and fine microstructure. It is found that dispersant content, solid loading and oil to water ratio of Pickering emulsions play vital roles on the controlling of pore morphology and pore size distribution of final hydroxyapatite ceramic foams. The multi-stage pores consist of millimeter-scale pores designed by 3D models and micro-pores below 10 µm derived from emulsion droplets. Due to the integration of hierarchical pores at different scale levels and micropores, hydroxyapatite ceramic foams possess outstanding compressive strength of 4.46–8.03 MPa at porosity of 76.59-72.96%. In vitro cell experiments illustrate that rat bone mesenchymal stem cells can spread and adhere to bio-scaffolds, promoting cell proliferation effectively and further verifying their good biocompatibility.