Impact of Dual-coated Silver Nanoparticle and Antibiotic Sutures on Wound Healing in Inflammatory Mouse Models

Background: The use of silver nanoparticles (AgNPs) in biomedicine has emerged in a big way owing to its antibacterial and anti-inflammatory properties. We hypothesize that combining the AgNPs with antibiotics for coating sutures will enhance the antibacterial property of sutures with the added advantage of the immunomodulatory effect of AgNPs on tissue healing.

Materials and methods: Polyglactin sutures were coated with AgNPs using the dip-coating method. The uniform coating and morphology of AgNPs on the suture surface were confirmed using scanning electron microscopy (SEM). Each type of suture - polyglactin plain, antibiotic coated (Triclosan), AgNP coated, and dually coated (antibiotic and AgNP) - was assessed for their antibacterial properties against Gram-positive bacteria, Gram-negative bacteria, and anaerobes. These sutures were utilized in an abdominal and systemic inflammatory mice model for ileal anastomosis. The intestinal tissue was evaluated for acute and chronic inflammation and collagen deposition to assess the healing and inflammatory response.

Results: The SEM and energy dispersive X-ray analysis showed successful coating of AgNPs on plain and antibiotic-coated sutures. In comparison with the other groups, the dually coated suture had the best in vitro antibacterial efficacy. The AgNP-coated sutures were able to decrease both acute and chronic inflammatory cell infiltration, but the collagen synthesis and deposition were enhanced.

Conclusion: AgNPs can be coated on Polyglactin suture either alone or in combination with antibiotics with preserved antibacterial effects. The dual coating of sutures gives a synergistic antibacterial effect. The AgNP diminishes immune response in the presence of preserved extracellular matrix generation.