A novel composite of collagen-hydroxyapatite/kappa-carrageenan

This study was to obtain Collagen-Hydroxyapatite/kappa-Carrageenan (COL- HAP/KCAR) composite with similar to those of natural bone. After been extracted from rabbit skins, the collagen was used in combination with Ca(NO3)2 and (NH4)2HPO4 to obtain COL-HAP composite in situ. kappa-Carrageenan, a kind of plant-polysaccharides, was also employed to improve the properties of the composite. Influences of preparing conditions on the microstructure of the composite and the bonding formation of HAP particles with collagen were characterized by XRD, SEM, and FT-IR. The properties of COL-HAP/KCAR composite, such as mechanical properties, hygroscopicity, degradable properties, and cytotoxicity were studied. XRD and SEM results showed that the inorganic phases of the composite were mainly hydroxyapatite well distributing on the biopolymer. FT-IR indicated that the NH and COO- of collagen may be the nucleation sites in mineralization. kappa-Carrageenan may act as a cross-linking agent, which decreased the hygroscopicity and biodegradability of COL-HAP (p < 0.01). The studies on the mechanical properties, hygroscopicity, biodegradability, cytotoxicity and haemolytic phenotype indicated that the material is a potential bone repair material.