Redox-Responsive Hydrogels Loaded with an Antibacterial Peptide as Controlled Drug Delivery for Healing Infectious Wounds

Abstract

Infectious wounds occur when harmful microorganisms such as bacteria or viruses invade a wound site. Its problems associated include delayed healing, increased pain, swelling, and the potential for systemic infections. Therefore, developing new wound dressing materials with antibacterial effects is crucial for improving the healing process. Here a redox-degradable hydrogel loaded with an antibacterial peptide (vancomycin) in a straightforward gram-scale synthesis, is developed. The hydrogel structure consists of a disulfide bond-containing hyperbranched polyglycerol (SS-hPG) that is cross-linked by 4-arm polyethylene glycol-thiol (4-arm PEG-SH). The polymerization mechanism and full characterization of SS-hPG are described as this synthesis is reported for the first time. Rheology is used to ascertain the hydrogel's mechanical characteristics, such as stiffness, and self-healing, determining these properties for different ratios and concentrations of both gel components. The incorporation of disulfide bonds in the hydrogel is proved by conducting degradation experiments in reductive environments. Fluorescein isothiocyanate-albumin (FITC-BSA) and vancomycin both are loaded into the gel, and the guest release kinetics is assessed for both slow and on-demand releases. Finally, the in vitro and in vivo experiments prove that the vancomycin-loaded hydrogel acts as an antibacterial barrier for wound dressing and accelerates the healing of infectious wounds in a mouse model.