Interpenetrating network gelatin methacryloyl (GelMA) and pectin-g-PCL hydrogels with tunable properties for tissue engineering

Biomater Sci. 2018 Oct 24;6(11):2938-2950. doi: 10.1039/c8bm00474a.

Abstract

The design of new hydrogel-based biomaterials with tunable physical and biological properties is essential for the advancement of applications related to tissue engineering and regenerative medicine. For instance, interpenetrating polymer network (IPN) and semi-IPN hydrogels have been widely explored to engineer functional tissues due to their characteristic microstructural and mechanical properties. Here, we engineered IPN and semi-IPN hydrogels comprised of a tough pectin grafted polycaprolactone (pectin-g-PCL) component to provide mechanical stability, and a highly cytocompatible gelatin methacryloyl (GelMA) component to support cellular growth and proliferation. IPN hydrogels were formed by calcium ion (Ca2+)-crosslinking of pectin-g-PCL chains, followed by photocrosslinking of the GelMA precursor. Conversely, semi-IPN networks were formed by photocrosslinking of the pectin-g-PCL and GelMA mixture, in the absence of Ca2+ crosslinking. IPN and semi-IPN hydrogels synthesized with varying ratios of pectin-g-PCL to GelMA, with and without Ca2+-crosslinking, exhibited a broad range of mechanical properties. For semi-IPN hydrogels, the aggregation of microcrystalline cores led to formation of hydrogels with compressive moduli ranging from 3.1 to 10.4 kPa. For IPN hydrogels, the mechanistic optimization of pectin-g-PCL, GelMA, and Ca2+ concentrations resulted in hydrogels with comparatively higher compressive modulus, in the range of 39 kPa-5029 kPa. Our results also showed that IPN hydrogels were cytocompatible in vitro and could support the growth of three-dimensionally (3D) encapsulated MC3T3-E1 preosteoblasts in vitro. The simplicity, technical feasibility, low cost, tunable mechanical properties, and cytocompatibility of the engineered semi-IPN and IPN hydrogels highlight their potential for different tissue engineering and biomedical applications.

MeSH terms

  • Biocompatible Materials / chemistry
  • Cell Line
  • Cell Proliferation
  • Cross-Linking Reagents / chemistry
  • Gelatin / chemistry*
  • Humans
  • Hydrogels / chemical synthesis
  • Hydrogels / chemistry*
  • Materials Testing
  • Molecular Weight
  • Pectins / chemistry*
  • Photochemical Processes
  • Polyesters / chemistry*
  • Polymerization
  • Polymethacrylic Acids / chemistry*
  • Surface Properties
  • Tissue Engineering / methods*
  • Tissue Scaffolds / chemistry

Substances

  • Biocompatible Materials
  • Cross-Linking Reagents
  • Hydrogels
  • Polyesters
  • Polymethacrylic Acids
  • polycaprolactone
  • Pectins
  • Gelatin