Polydopamine-Assisted ZnTiO-ZnO Heterostructure Formation on Titanium with Decent Osteogenic and Antibacterial Activity.

Implant-associated infections and inadequate osseointegration are major contributors to orthopedic implant failures. Although hydrothermally grown zinc oxide (ZnO) nanorods on titanium (Ti) implants enhance antibacterial activity, their aggressive degradation and uncontrolled Zn leaching do not meet the requirements for bone implants and can damage the surrounding tissues. This study introduces a crystal-damage-free nanoengineering mechanism to enhance the stability of ZnO nanorods by utilizing a carbon nanolayer as a sacrificial template between the ZnO core and TiO. This mechanism induced the formation of a hybrid ZnTiO heterostructure within the carbon layer at a low temperature of 500 °C by reducing the required activation energy. This carbon layer acts as a diffusion barrier, allowing the unilateral diffusion of ZnO into TiO while preventing Ti diffusion into the ZnO core. The resulting ZnO@TiO-6 heterostructure controlled Zn leaching and exhibited significant osteogenic activity of MC3T3-E1 cells and potent antibacterial efficacy against and due to the differential landscape of osteoblasts and bacteria. studies further confirm that ZnO@TiO-6 heterostructure eradicated 90% of bacteria, alleviated inflammation, and enhanced biocompatibility. Unlike Ti implants, which lack antibacterial properties, and ZnO alone, which induces inflammation, ZnO@TiO-6 nanorods provide enhanced stability, sustained Zn release, optimized ROS levels, and dual antibacterial and osteogenic functions, making them a promising advancement for orthopedic and dental implants.