Preparation of Copper-Doped Hydroxyapatite with Varying x in the Composition Ca10(PO4)6CuxOyHz

Copper (Cu) ions are of interest with respect to materials for bone regeneration because of their pro-angiogenic potential. One of the problems with synthetic bone scaffolds is the fast decrease in viability of cells with increasing distance from the surface of the scaffold material, which results from the inability of nutrients and oxygen to diffuse further than 150-200 μm from the surface without a blood supply [1]. Stimulating infiltration of blood vessels into a bone substitute scaffold, therefore, could increase the viability of bone forming cells within the scaffold and so hasten the healing process. Recently, the preparation of CuSO4-loaded calcium phosphate scaffolds and of Cu-doped solgel bioactive glasses for this purpose has been reported [2,3]. Here we report the preparation of hydroxyapatite structurally doped with Cu ions, with the aim of developing a bio-instructive scaffold. In order to tune the biological response to the material, the rate and amount of ion release needs to be controlled: the first step in this task is to prepare materials with varying dopant levels. We have prepared Cudoped hydroxyapatite with x=0, 0.5, 0.75 and 1 in the nominal formula Ca10(PO4)6CuxOyHz by solid state synthesis. Materials and Methods