Novel method for the fabrication of multiscale structure collagen/ hydroxyapatite-microsphere composites based on CaCO_3 microparticle templates

摘要

A synthesis strategy based on the phase transformation of calcium carbonate (CaCO_3) microparticle tem-plates was developed for the fabrication of collagen/hydroxyapatite (HA)-microsphere composite materials, which were derived from prefabricated collagen/CaCO_3-microparticle hybrid gels in a phosphate ambience. Fourier transform infrared spectroscopy and X-ray diffraction analyses were conducted to confirm the forma-tion of carbonated hydroxyapatite in the collagen/HA-microsphere composites. The variations in the contents of inorganic components after the transformation of CaCO_3 templates into calcium phosphate were further validated via thermogravimetric analysis. Scanning electron microscopy characterization revealed the unique multiscale microstructures of the collagen/HA-microsphere composites, which comprised collagen nanofibril networks and HA microspheres. The synthesis strategy is suitable for the in situ synthesis of microscale apatite components within a collagen-based biomacromolecule matrix under mild conditions.