Hybrid coatings of poly(L-lysine) and apatite on micro-arc oxidized titania

Hybrid coatings of poly(L-lysine) and apatite were formed on the micro-arc oxidized titania through a biomimetic process. Phosphorous (P)-containing titania films were prepared by micro-arc oxidation (MAO) of titanium (Ti) substrates in an electrolyte solution containing β-glycerol phosphate disodium salt pentahydrate. The hybrid coatings were grown by immersing MAO titania in the poly(L-lysine)-containing simulated body fluid (SBF) solution. After 72 h immersion, the globular precipitates appeared on the surface of titania films and grew up to ~ 10 µm. These precipitates consisted of 100–200 nm nano-flakes with a distorted (less straight) morphology. XRD and FT-IR confirmed that these precipitates were poly(L-lysine)-containing apatite nanocomposite.