Black tantalic oxide submicro-particles coating on PEEK fibers woven into fabrics as artificial ligaments with photothermal antibacterial effect and osteogenic activity for promoting ligament-bone healing

Design of artificial ligaments possessing both osteogenic activity and antibacterial effect that promotes ligament-bone healing and prevents bacterial infection in bone tunnels for anterior cruciate ligament (ACL) reconstruction remains a significant challenge. In this study, black tantalic oxide (BTO) submicro-particles with oxygen vacancies and structure defects were fabricated by using traditional white tantalic oxide (WTO) through magnesium thermal reduction (MTR) method, and BTO was coated on polyetheretherketone (PEEK) fibers (PKF), which were woven into fabrics (PBT) as artificial ligaments. PBT with BTO coating exhibited excellent photothermal performance, which possessed not only antibacterial effects in vitro but also anti-infective ability in vivo. PBT with optimized surface properties (e.g., submicro-topography and hydrophilicity) not only significantly facilitated rat bone mesenchymal stem cells (BMSC) responses (e.g., proliferation and osteogenic differentiation) in vitro but also stimulated new bone formation for ligament-bone healing in vivo. The presence of oxygen vacancies and structure defects in BTO did not change the surface properties and osteogenic activity of BPT while displaying an outstanding photothermal antibacterial effect. In summary, BPT with osteogenic activity and photothermal antibacterial effect promoted bone regeneration and prevented bacterial infection, thereby promoting ligament-bone healing. Therefore, PBT would have tremendous potential as a novel artificial ligament for ACL reconstruction.