Interconnected Hydroxyapatite Nanofibers in the Biomimetic Coating of a Bioinert Ceramic Substrate

Abstract

A bioinert ceramic substrate, α‐Al2O3, has been coated with hydroxyapatite (HAp) by the biomimetic route using simulated body fluid (SBF) solution at room temperature. The substrate was incubated at 37°C in SBF for 6 days with a periodic replacement with freshly prepared SBF at 48‐h intervals. After 6 days, continuous nanofiber‐like structures of HAp (5–35 μm in length, 0.05 μm diameter) were obtained, connecting the intra‐ and interglobular clusters, within the coated mineral layer on the substrate surface. This is a unique and new observation, and this phenomenon has been demonstrated by a simple fractal growth model.