Drug release from polymer-coated TiO₂ nanotubes on additively manufactured Ti-6Al-4V bone implants: a feasibility study

Abstract Insufficient osseointegration, inflammatory response and bacterial infection are responsible for the majority of bone implant failures. Drug-releasing implants subjected to adequate surface modification can concurrently address these challenges improve success surgeries. This work investigates use Ti-6Al-4V (Ti64) with a dual-scale topography as platform local drug delivery. Dual-scale was obtained combining inherent microscale roughness Ti64 samples manufactured by selective laser melting (SLM) nanoscale TiO 2 nanotubes (TNTs) subsequent electrochemical anodization at 60 V 30 min. TNTs were loaded solution penicillin-streptomycin, common antibiotic, release tested in vitro. Three biocompatible biodegradable polymers, i.e. chitosan, poly(ε-caprolactone) poly(3-hydroxybutyrate), deposited spin coating, while preserving substrate underneath. The presence polymer coatings overall modified pattern, revealed fitting experimental data power-law model. A slight extension duration (about 17% single layer 33% two layers PCL PHB) reduced burst observed all polymer-coated compared uncoated, especially when applied.