Electro-responsive graphene oxide hydrogels for skin bandages: The outcome of gelatin and trypsin immobilization

Int J Pharm. 2018 Jul 30;546(1-2):50-60. doi: 10.1016/j.ijpharm.2018.05.027. Epub 2018 May 11.

Abstract

A free radical polymerization method was adopted for the fabrication of hybrid hydrogel films based on acrylamide and polyethylene glycol dimethacrylate as plasticizing and crosslinking agents, respectively, to be employed as smart skin bandages. Electro-sensitivity, biocompatibility and proteolytic properties were conferred to the final polymer networks by introducing graphene oxide (0.5% w/w), gelatin or trypsin (10% w/w) in the polymerization feed. The physical chemical and mechanical characterization of hybrid materials was performed by means of determination of protein content, Raman spectroscopy, thermogravimetric analysis and measurement of tensile strength. The evaluation of both water affinity and curcumin release profiles (analyzed by suitable mathematical modelling) upon application of an external electric stimulation in the 0-48 voltage range, confirmed the possibility to modulate the release kinetics. Proper proteolytic tests showed that the trypsin enzymatic activity was retained by 80% upon immobilization. Moreover, for all samples, we observed a viability higher than 94% in normal human fibroblast cells (MRC-5), while a reduction of methicillin-resistant Staphylococcus aureus CFU mL-1 (90%) was obtained with curcumin loaded samples.

Keywords: Antimicrobial; Curcumin; Electro-responsive release; Enzyme immobilization; Graphene oxide; Hybrid hydrogels.

MeSH terms

  • Acrylamide / administration & dosage
  • Acrylamide / chemistry
  • Bandages*
  • Cell Line
  • Cell Survival / drug effects
  • Curcumin / administration & dosage
  • Curcumin / chemistry
  • Drug Liberation
  • Fibroblasts / drug effects
  • Gelatin / administration & dosage*
  • Gelatin / chemistry
  • Graphite / administration & dosage*
  • Graphite / chemistry
  • Humans
  • Hydrogels / administration & dosage*
  • Hydrogels / chemistry
  • Methacrylates / administration & dosage
  • Methacrylates / chemistry
  • Methicillin-Resistant Staphylococcus aureus / drug effects
  • Methicillin-Resistant Staphylococcus aureus / growth & development
  • Oxides / administration & dosage*
  • Oxides / chemistry
  • Polyethylene Glycols / administration & dosage
  • Polyethylene Glycols / chemistry
  • Polymerization
  • Spectrum Analysis, Raman
  • Tensile Strength
  • Thermogravimetry
  • Trypsin / administration & dosage*
  • Trypsin / chemistry

Substances

  • Hydrogels
  • Methacrylates
  • Oxides
  • poly(ethylene glycol)-dimethacrylate
  • Acrylamide
  • Polyethylene Glycols
  • Graphite
  • Gelatin
  • Trypsin
  • Curcumin