Antibacterial Surgical Silk Sutures Using a High-Performance Slow-Release Carrier Coating System

Area of Science:

• Biomaterials Science
• Surgical Innovation
• Infectious Disease Prevention

Background:

• Surgical site infections are a significant postoperative concern.
• Antibacterial sutures reduce infection complications.
• Triclosan-free alternatives are emerging, necessitating new antibacterial agents.

Purpose of the Study:

• To optimize novel antibacterial braided silk sutures using levofloxacin hydrochloride and poly(ε-caprolactone).
• To achieve slow-release antibacterial efficacy and ideal physical/handling properties.
• To evaluate two different processing sequences (M1 and M2 groups).

Main Methods:

• Silk sutures were braided and treated with antibacterial agents via a two-dipping-two-rolling method before (M1) or after (M2) braiding.
• Antibacterial activity against Staphylococcus aureus and Escherichia coli was assessed.
• Drug release profiles, knot-pull tensile strength, friction, bending stiffness, and cytotoxicity were evaluated.

Main Results:

• All coated sutures demonstrated continuous antibacterial efficacy and slow drug release (>5 days).
• Treated sutures met U.S. Pharmacopoeia tensile strength requirements.
• The M1 group exhibited minimal changes in physical/handling properties compared to uncoated sutures, while M2 approached monofilament characteristics.

Conclusions:

• Novel levofloxacin hydrochloride and poly(ε-caprolactone) coated sutures show potential as antibacterial materials.
• The M1 processing method offers a promising prospect for clinical applications due to favorable properties.
• Sustained drug release and antibacterial activity were successfully achieved.