| Summary: | Trabajo presentado en Granada Münster Discussion Meeting, celebrado en Münster (Alemania), del 29 al 30 de noviembre de 2018 Ideal materials for bone tissue engineering can be obtained through the pseudomorphic mineral replacement of carbonate biological hard tissues by apatite. During this process the internal hierarchically arranged porosity of carbonate biological hard tissues is preserved.1-4 Interestingly, both pore sizes and pore distribution of these materials closely match those required for bone grafting. In this work we present results on the kinetics of the transformation of a variety of coral bioaragonite skeletons into apatite scaffolds after interaction with boiling phosphate-bearing aqueous solutions. We used the skeletons of four different corals in our experiments. The two warm water corals Acropora sp. and Porites sp. and the two cold water corals Lophelia pertusa and Madrepora oculata. Coral skeletons are organic-inorganic composites that show distinct function-related characteristics, regarding their microstructure, skeletal density, original porosity and content of organic biopolymers. These distinct features have a complex influence on the skeleton reactivity. In this work we focus on the organic content of the coral skeletons and discuss its role in defining the kinetics of the mineral replacement. Mineral replacement experiments lasted for 14 days. Samples were collected after 4, 7, 9 and 14 days of transformation periods. Both, pristine and transformed samples were characterized using X-ray powder diffraction (XRPD), FTIR-spectroscopy analysis and Scanning Electron Microscopy (SEM) imaging. Thermo Gravimetrical analyses (TGA) were conducted to determine their content of organics. Furthermore, their surface area (SA) and porosity was analysed by nitrogen (N2) adsorption measurements. All pristine samples consist of aragonite. The highest content of organics corresponds to the pristine sample of Madrepora oculata, with 6.05%, followed by Lophelia pertusa, with 4.93%. These contents ...
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