Translator Bioabsorbable Anti-Infection System for Orthopedic Implants

Infections in implant surgeries represent serious complications, accounting for approximately 20% of orthopedic implant failures. Conventional treatment is systemic and requires high doses of antibiotics. Controlled drug delivery emerges as a promising alternative, particularly in fighting the formation of bacterial biofilms, which are highly resistant to antibiotic action. Bioabsorbable and biocompatible polymers, such as poly(lactic-co-glycolic acid) (PLGA) and poly(L-co-D,L-lactic acid) (PLDLA), show great potential for this purpose. Rifampicin (RIF), a broad-spectrum antibiotic, is effective against S. aureus and S. epidermidis , acting by inhibiting bacterial RNA synthesis and penetrating biofilms. This study developed an anti-infection system (AIS) in the form of membranes based on PLGA and PLDLA, incorporating 0.5% and 1% RIF. Thin membranes (15–40 µm) were obtained. RIF did not promote molecular interactions with the polymers nor significantly alter their thermal stability. The materials did not exhibit antimicrobial activity against E. coli ; however, with 1% RIF, they reached the minimum biofilm-inhibitory concentration (MBIC) against S. aureus . PLDLA proved suitable for slow drug release at low concentrations, whereas PLGA enabled a more intense release after two weeks.