Peptide-Immobilized Core-Sheath Architecture Sutures with Enhanced Mechanical Strength and Antimicrobial Activity

To address surgical site infections (SSIs), we developed a core-sheath suture via electrospinning consisting of a robust silk core for mechanical strength and a functionalized polycaprolactone (PCL) nanofiber sheath. The antimicrobial peptide KR-12 was covalently immobilized onto the sheath, enabling potent antibacterial activity while mitigating cytotoxicity. The suture exhibited broad-spectrum efficacy against Gram-positive and Gram-negative bacteria, including MRSA, and significantly inhibited biofilm formation. It provided sustained antibacterial performance for up to 14 days, with over 97% inhibition against Escherichia coli and Staphylococcus aureus. Additionally, this demonstrated favorable cytocompatibility. In infected skin wounds, the suture promoted healing by reducing inflammatory infiltration, stimulating collagen regeneration, and downregulating TNF-α expression. This mechanically strong, biocompatible, and persistently antibacterial suture offers a promising strategy for the prevention of SSIs.