Microstructure and chemical states of hydroxyapatite/silk fibroin nanocomposites synthesized via a wet-mechanochemical route

Hydroxyapaptite (HAp)/silk fibroin (SF) nanocomposites were prepared via a wet-mechanochemical route at room temperature. The results reveal that the inorganic phase in the composites is carbonate-substituted HAp containing 2.9-3.1 wt% of carbonate ions. The primary HAp crystals are rod-like in shape with a typical size of 20-30 nm in length and 8-10 nm in width, and lattice parameters a = 9.423 Angstrom, c = 6.888 Angstrom. The self-assembled HAp crystals along their c-axes aggregate into bundles, which are connected with SF fibrils. Consequently, a three-dimensional porous network is formed in the composite, which is beneficial to inducing new bone formation in practical implantation.