Preparation and characterization of macroporous magnesium phosphate scaffold for bone regeneration

Abstract

Much attention has been focused on the biomedical applications of magnesium phosphate cement (MPC) as bone substitution material. The use of porous scaffolds with characteristics such as high porosity along with macropores and three-dimensional interconnected pore structures is beneficial for repairing bone defects. MPC has been proven to be degradable and biocompatible, and therefore might be applied as three-dimensional scaffolds for bone regeneration. In this study, macroporous MPC scaffolds were fabricated by the particle leaching method using sodium chloride as porogen. The morphology, chemical composition and cellular response to the scaffolds were investigated. The obtained scaffolds had a well-interconnected porous structure with pore sizes ranging from 400 to 600μm. The porosities of the scaffolds determined using the Archimedes’s Principle could reach 71%. X-ray diffraction pattern revealed that the main composition of the obtained scaffold was NH4MgPO4•6H2O. MTT tests demonstrated that the osteoblast-like cell proliferation rate was higher on the macroporous MPC scaffolds than on the controls at 3 and 7 days of culture. Scanning electron microscopy showed the significant cell adhesion, spreading and growth in the macroporous MPC scaffolds. The cell culture experiments indicated that the macroporous MPC scaffolds could promote osteoblast-like cell attachment and proliferation, exhibiting good in vitro biocompatibility. These results suggest that the macroporous MPC scaffolds may have potential applications for bone regeneration.