Design of antimicrobial peptides conjugated biodegradable citric acid derived hydrogels for wound healing

Wound healing is usually facilitated by the use of a wound dressing that can be easily applied to cover the wound bed, maintain moisture, and avoid bacterial infection. In order to meet all of these requirements, we developed an in situ forming biodegradable hydrogel (iFBH) system composed of a newly developed combination of biodegradable poly(ethylene glycol) maleate citrate (PEGMC) and poly(ethylene glycol) diacrylate (PEGDA). The in situ forming hydrogel systems are able to conform to the wound shape in order to cover the wound completely and prevent bacterial invasion. A 2(k) factorial analysis was performed to examine the effects of polymer composition on specific properties, including the curing time, Young's modulus, swelling ratio, and degradation rate. An optimized iFBH formulation was achieved from the systematic factorial analysis. Further, in vitro biocompatibility studies using adult human dermal fibroblasts (HDFs) confirmed that the hydrogels and degradation products are not cytotoxic. The iFBH wound dressing was conjugated and functionalized with antimicrobial peptides as well. Evaluation against bacteria both in vitro and in vivo in rats demonstrated that the peptide-incorporated iFBH wound dressing offered excellent bacteria inhibition and promoted wound healing. These studies indicated that our in situ forming antimicrobial biodegradable hydrogel system is a promising candidate for wound treatment.