Antioxidant and multi-sensitive PNIPAAm/keratin double network gels for self-stripping wound dressing application

J Mater Chem B. 2021 Aug 21;9(31):6212-6225. doi: 10.1039/d1tb00702e. Epub 2021 Jul 28.

Abstract

Hydrogel is a potential wound dressing material due to its ability to maintain a humid environment, the strong absorptive capacity of exuded tissue fluid, and gas exchange function. Herein, poly(N-isopropyl acrylamide)/keratin double network (PNIPAAm/keratin DN) gels were fabricated through covalent and ionic double cross-linking strategy. The effects of PNIPAAm/keratin ratios on the morphology and swelling rate of gels were characterized. The DN gels could swell up from 2600% to 4600% in proportion to the keratin content, demonstrating their great ability to absorb tissue fluid. The gels possessed thermo-sensitiveness, imparting self-stripping property. Moreover, the antibacterial chlorhexidine acetate (CHX) was loaded into gels with a post-fabrication drug-loading strategy. The release behavior showed that CHX-loaded DN gels exhibited multiple responsive characteristics (temperature, pH, and ROS). Furthermore, the drug-loaded gels showed greater antibacterial activity than free CHX due to the sustained drug release effect. Meanwhile, the antioxidant efficiency of PNIPAAm/keratin DN gels was ca. 33.1%, while the PNIPAAm gel was just ca. 18.2%, indicating the strong oxidation resistance of DN gels. In the Sprague Dawley (SD) rat skin defect model, the hydrogel had better tissue regeneration ability than the commercial film. Taken together, the multifunctional PNIPAAm/keratin DN gels are potential candidates for clinical wound treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acrylic Resins / chemistry
  • Acrylic Resins / pharmacology*
  • Animals
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Antioxidants / chemistry
  • Antioxidants / pharmacology*
  • Bandages
  • Biocompatible Materials / chemistry
  • Biocompatible Materials / pharmacology*
  • Biphenyl Compounds / antagonists & inhibitors
  • Hydrogels / chemistry
  • Hydrogels / pharmacology*
  • Keratins / chemistry
  • Keratins / pharmacology*
  • Materials Testing
  • Picrates / antagonists & inhibitors
  • Rats
  • Rats, Sprague-Dawley
  • Wound Healing / drug effects

Substances

  • Acrylic Resins
  • Anti-Bacterial Agents
  • Antioxidants
  • Biocompatible Materials
  • Biphenyl Compounds
  • Hydrogels
  • Picrates
  • poly-N-isopropylacrylamide
  • Keratins
  • 1,1-diphenyl-2-picrylhydrazyl