Strategically prolonged release of multiple antibacterial components from a thin film coating for synergistic effects against Staphylococcus aureus infections

Biomaterial-associated infections (BAIs) remain a major challenge in clinical surgery because they can potentially cause serious disabilities in patients. This study investigated the use of a multilayer coating technology that can co-deliver two therapeutic components, gentamicin and OP-145 peptide, to treat Staphylococcus aureus effectively. A biocompatible and biodegradable thin film was produced via layer-by-layer assembly using an antibacterial peptide and gentamicin. The thin film was systematically characterized, showing controllable features such as thickness, transparency, cargo loading, and cargo release. In vitro tests showed that the thin film has fewer toxicity problems than soluble cargos; compared to cargos in a soluble form, the thin film has minor impacts on mammalian cells' metabolism. Additionally, the antibacterial cargos assembled on the thin film can effectively inhibit the formation of biofilms and show effective in vitro antibacterial potency. In vivo studies illustrated that the thin film can inhibit the progression of S. aureus in a mouse model, indicating the effectiveness of the thin film structure in the clinic. This study demonstrates that a thin film composed of gentamicin and OP-145 could be employed to prevent BAIs in clinical surgery.