Tailoring the biological performance of titanium implants via a TaCu nanocoating on MAO-porous layers: the interplay between surface topography and controlled Cu2+ release.

Titanium (Ti) is widely used in oral implants but is limited by insufficient osteogenic activity, angiogenic capacity, and antibacterial performance. To address this, pure Ti was modified by micro-arc oxidation (MAO) to form a porous layer, followed by magnetron sputtering of a TaCu nanocoating under different conditions to prepare three composite samples (MAO-Ti/TaCu1, MAO-Ti/TaCu4, and MAO-Ti/TaCu7). The samples were characterized for surface properties and Cu2+ release, and their biological performance was evaluated via in vitro experiments. Results showed that MAO-Ti/TaCu coatings maintained the MAO porous structure and achieved cytocompatible, sustained Cu2+ release. MAO-Ti/TaCu4 exhibited optimal osteogenic activity, with the highest cell viability, ALP activity, matrix mineralization, and expression of osteogenic-related genes (ALP, Runx2, Col-I, and OPN). MAO-Ti/TaCu7 showed the strongest angiogenic capacity, reflected by superior HUVEC morphology, migration, and angiogenic-related gene (eNOS, VEGF, and FGFR1) expression. All TaCu-modified groups had significant antibacterial activity. The enhanced performance was attributed to the synergistic effect of the porous MAO layer and TaCu nanocoating, with moderate Cu2+ release favoring osteogenesis and higher release promoting angiogenesis. This study provides a new strategy for titanium implant surface modification to improve osseointegration.