Green synthesis of degradable conductive thermosensitive oligopyrrole/chitosan hydrogel intended for cartilage tissue engineering

Int J Biol Macromol. 2018 Feb;107(Pt B):1567-1575. doi: 10.1016/j.ijbiomac.2017.10.015. Epub 2017 Oct 10.

Abstract

Electroactive scaffolds containing conductive polymers can promote tissue repair and regeneration. However, these polymers are non-degradable and cannot be removed from body. To overcome this limitation of conductive polymers, we developed a novel injectable electroactive hydrogel containing pyrrole oligomers which possessed the unique properties of being both electrically conductive and biodegradable. First, pyrrole oligomers were synthesized via chemical polymerization and were found to be amorphous with a non-globular morphology. Then, three different compositions of injectable chitosan/beta glycerophosphate hydrogels containing different concentrations of pyrrole oligomers were synthesized and characterized for chemical structure, morphology, conductivity, swelling ratio, In vitro biodegradation and gelation time. An increase in oligopyrrole content resulted in decreased pore size, and increased gelation time, swelling ratio, conductivity and degradation time. Among all the hydrogel compositions, the sample with pyrrole oligomer:chitosan ratio of 0.1 (w/w) showed the most prominent biodegradability, biocompatibility, electro-activity, swelling ratio and pore size values and was chosen as the optimal electroactive hydrogel composition in this work.

Keywords: Chitosan; Conductive thermosensitive; Hydrogel; Pyrrole oligomer.

MeSH terms

  • Animals
  • CHO Cells
  • Cartilage / physiology*
  • Cell Survival
  • Chitosan / chemistry*
  • Cricetinae
  • Cricetulus
  • Electric Conductivity*
  • Fibroblasts / cytology
  • Freeze Drying
  • Green Chemistry Technology / methods*
  • Hydrogel, Polyethylene Glycol Dimethacrylate / chemistry*
  • Hydrogen-Ion Concentration
  • Pyrroles / chemical synthesis
  • Pyrroles / chemistry*
  • Solubility
  • Spectrophotometry, Ultraviolet
  • Spectroscopy, Fourier Transform Infrared
  • Temperature*
  • Time Factors
  • Tissue Engineering / methods*
  • X-Ray Diffraction

Substances

  • Pyrroles
  • Hydrogel, Polyethylene Glycol Dimethacrylate
  • Chitosan