(11f) ‘Two-in-One' Multilayer Coatings for Prosthesis-Related Infections

Prosthetic joint replacement is increasingly used to alleviate pain and to improve mobility. Infections associated with prosthetic joints, however, cause significant morbidity and account for a large proportion of healthcare expenditures. Conventional two-stage revision is widely accepted as a technique of choice for infection treatment, but an optimal strategy for simple, safe, and economical revision remains elusive. Here we report an approach for one-stage revision using implants coated with a self-assembled, polymer-based bioactive coating carrying antibiotic gentamicin sulfate (GS), osteoinductive bone morphogenetic protein-2 (BMP-2), and hydrolytically degradable polymers. A multilayered coating was assembled using a water-based layer-by-layer approach, in which each element was deposited on the surface in nanoscale layers. The controlled, localized release of GS was essential to eliminate infection and to protect the implant against re-infection for multiple weeks; furthermore, the subsequent release of BMP-2 enabled the rapid and complete integration of new well-developed trabecular bone around the implant. These ‘Two-in-One’ multilayer coatings protected the implant against continuing threats of bacteria over time, facilitated early deposition of bone on the implant, and had significantly higher bone-implant interfacial tensile strength and long-term mechanical stability than the uncoated control implants, indicating the potential of this strategy for single-stage treatment of prosthesis-related infections for revision arthroplasty.