Turning dextran into antibacterial fibers: Quaternary ammonium salt for antibacterial treatment and wound healing

This study aims to develop new quaternary ammonium salt-based antimicrobial materials with good biocompatibility, biosafety, and strong antimicrobial properties that promote wound healing in infected wounds. First, four new quaternary ammonium salt antibacterial fibers (QASAF) are constructed: QASAF-C12, QASAF-C14, QASAF-C16, and QASAF-C18, with varying carbon chain lengths of C12, C14, C16, and C18, respectively. Then, their structure is characterized by proton nuclear magnetic resonance (NMR) analysis and their hemolytic and cytotoxic properties are also investigated. QASAFs are then evaluated for in vivo and in vitro antimicrobial performance against Staphylococcus aureus (S. aureus) and methicillin-resistant Staphylococcus aureus (MRSA). Finally, the effect of QASAF on promoting wound healing in infected wounds is evaluated using mouse wound models infected with S. aureus and MRSA. The obtained results suggest that QASAF is non-toxic to cells in the 25–125 µg/mL concentration range, is slightly hemolytic, has good biocompatibility, and has a biosafety profile. QASAF-C18 shows the best antibacterial performance against S. aureus with significant pro-healing effects on infected wounds. QASAF-C12 exhibits the best antibacterial performance against MRSA with significant pro-healing effects. The novel quaternary ammonium-based antimicrobial material provides a reference for developing antimicrobial and biocompatible wound dressings.