Calciumphosphate : Synthese, Reaktionen in wässrigen Medien und Charakterisierung von Oberflächen und Grenzflächen

Calciumphosphate biomaterials are very important components repairing the mineralised tissue of humans. The chemical, structural, mechanical, and functional properties of these materials are very similar to teeth and bones. The development of application-oriented and optimized implantable biomaterials (e.g. cements, ceramics and composite materials) in the system CaO-P2O5-H2O is of great importance. A detailed knowledge of chemical processes in this complex system can help us to understand, to a considerable extent, very important aspects of biomineralization. For this reason the investigation of hydration mechanisms, chemical reactions especially on interfaces, and the products arising, which are not yet well understood, is of outstanding importance.
This thesis covers three main aspects. First aspect is the understanding of structural relationships between calciumphosphates especially with respect to hydroxyapatite. Synthesis of the relevant phase-pure calciumphosphates is the second aspect. Third aspect is the investigation and characterization of calciumphosphate material surfaces, interfaces, and boundaries between calciumphosphate cements and denatured bone parts. This contains the observation of effects caused by solution, precipitation, crystallization, and transformation of phases and characterization of the interface regarding material properties as well. For these investigations especially high-resolution micro- and nanoscopic techniques (i.e. Scanning Probe Microscopy) and Rietveld analysis were performed.
The results regarding this thesis can be useful to develop and optimize calciumphosphate biomaterials. In addition they can be helpful to understand processes which influence the biocompatibility in the physiological environment.