Bioactive nanoengineered hydrogels for bone tissue engineering: a growth-factor-free approach

ACS Nano. 2015 Mar 24;9(3):3109-18. doi: 10.1021/nn507488s. Epub 2015 Feb 25.

Abstract

Despite bone's impressive ability to heal after traumatic injuries and fractures, a significant need still exists for developing strategies to promote healing of nonunion defects. To address this issue, we developed collagen-based hydrogels containing two-dimensional nanosilicates. Nanosilicates are ultrathin nanomaterials with a high degree of anisotropy and functionality that results in enhanced surface interactions with biological entities compared to their respective three-dimensional counterparts. The addition of nanosilicates resulted in a 4-fold increase in compressive modulus along with an increase in pore size compared to collagen-based hydrogels. In vitro evaluation indicated that the nanocomposite hydrogels are capable of promoting osteogenesis in the absence of any osteoinductive factors. A 3-fold increase in alkaline phosphatase activity and a 4-fold increase in the formation of a mineralized matrix were observed with the addition of the nanosilicates to the collagen-based hydrogels. Overall, these results demonstrate the multiple functions of nanosilicates conducive to the regeneration of bone in nonunion defects, including increased network stiffness and porosity, injectability, and enhanced mineralized matrix formation in a growth-factor-free microenvironment.

Keywords: bone regeneration; nanocomposite hydrogels; scaffolds; synthetic nanosilicates; tissue engineering; two-dimensional (2D) nanoparticles.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Biocompatible Materials / chemistry
  • Biocompatible Materials / pharmacology
  • Bone and Bones / cytology*
  • Bone and Bones / drug effects*
  • Bone and Bones / physiology
  • Calcification, Physiologic / drug effects
  • Cell Adhesion / drug effects
  • Cell Line
  • Collagen / chemistry
  • Gelatin / chemistry
  • Hydrogels / chemistry*
  • Hydrogels / pharmacology*
  • Mechanical Phenomena
  • Mice
  • Nanocomposites / chemistry*
  • Nanotechnology / methods*
  • Osteogenesis / drug effects
  • Silicates / chemistry
  • Tissue Engineering / methods*

Substances

  • Biocompatible Materials
  • Hydrogels
  • Silicates
  • Gelatin
  • Collagen