Structural investigation on a new family of amorphous calcium ortho- and pyro-phosphates materials for bone substitution

Amorphous calcium phosphates have been extensively studied as bioactive bone substitute materials thanks to the biocompatibility and bioactivity of calcium orthophosphate phases. A few studies on calcium pyrophosphate biomaterials have demonstrated their promising biological properties through cell and animal studies and a clinical trial. Recently, we demonstrated the possibility to associate both ortho- and pyro-phosphates in the same amorphous material and the capability of this new family of materials to degrade and lead apatite formation in different acellular media. We propose to perform neutron diffraction with isotopic substitution experiments (in complement of X-ray experiments) and to determine the short range order around H and Ca atoms, which could allow us to solve the structure of these new amorphous materials that is crucial to predict their in vivo behaviour.