New Biocompatible Ti-MOF@hydroxyapatite Composite Boosted with Gentamicin for Postoperative Infection Control

The standard clinical management of osteomyelitis involves prolonged antibiotic therapy, which frequently necessitates the excision of infected tissues. However, the efficacy of such treatments is increasingly compromised by the rise of antibiotic-resistant pathogens, underscoring an urgent need for innovative approaches. This study introduces a novel composite material designed to offer dual functionality: robust antimicrobial activity and promotion of bone regeneration. The composite integrates biocompatible hydroxyapatite nanoparticles (HA) with a titanium(IV)-metal-organic framework, MIL-125(Ti)-NH₂, impregnated with gentamicin (GM). The solvothermally synthesized MIL-125-NH₂@HA composite demonstrates high cytocompatibility, as evidenced by assays using osteoblasts (U2-OS) and fibroblasts (L929), alongside an absence of hemolytic activity at concentrations of up to 1000 μg/mL. Importantly, the introduction of GM into the composite significantly amplifies its antibacterial efficacy against <i>Staphylococcus aureus</i> and <i>Pseudomonas aeruginosa</i>. Additionally, nanoindentation assessments reveal enhanced mechanical properties of the MIL-125-NH₂@HA composite, indicating the superior elastic performance relative to unmodified HA. The findings of this research are poised to generate significant interest in the development of metal-organic framework (MOF)-based composites for antimicrobial implant applications, presenting a promising avenue for addressing the challenges posed by antibiotic resistance in bone infections.