Chemical and structural investigations of biomimetically grown fluorapatite-gelatin composite aggregates

Deeper understanding of the basic principles of biomineralization is a major challenge for present and future research. The high complexity of in vivo conditions calls for simplifies model systems that still involve dynamic processes like reorganization, formation, self-organization, and development of patterns, respectively. The present contribution deals with hierarchically ordered spherical aggregates of fluorapatite-gelatin composites with fractal architecture that are grown in gelatin matrices. The model system was chosen to mimic formation conditions on a lower level of complexity compared with the natural formation of calcifies tissue (bone, teeth). In order to gain insight into structure formation and the motif for this special kind of morphogenesis we investigated the interaction of the organic and inorganic components of aggregates in different growth stages by detailed chemical analyses, thermoanalytical measurements, X-ray diffraction on solitary particles, and scanning electron microscopy (SEM) as well as transmission electron microscopy (TEM) investigations. the close relation of the results and observations to calcified tissue may stimulate advanced interests in the fields of medical and materials development.