Cotton-wool-like bioactive glasses for bone regeneration

Research output: Contribution to journalArticle

Authors

  • D. Wang
  • S. Li
  • J. Nakamura
  • R. Bradley
  • P. D. Lee
  • M. M. Stevens
  • David S. McPhail
  • Toshihiro Kasuga
  • J. R. Jones

Colleges, School and Institutes

External organisations

  • Imperial College London
  • Nagoya Institute of Technology
  • University of Manchester

Abstract

Inorganic sol–gel solutions were electrospun to produce the first bioactive three-dimensional (3-D) scaffolds for bone tissue regeneration with a structure like cotton-wool (or cotton candy). This flexible 3-D fibrous structure is ideal for packing into complex defects. It also has large inter-fiber spaces to promote vascularization, penetration of cells and transport of nutrients throughout the scaffold. The 3-D fibrous structure was obtained by electrospinning, where the applied electric field and the instabilities exert tremendous force on the spinning jet, which is required to be viscoelastic to prevent jet break up. Previously, polymer binding agents were used with inorganic solutions to produce electrospun composite two-dimensional fibermats, requiring calcination to remove the polymer. This study presents novel reaction and processing conditions for producing a viscoelastic inorganic sol–gel solution that results in fibers by the entanglement of the intermolecularly overlapped nanosilica species in the solution, eliminating the need for a binder. Three-dimensional cotton-wool-like structures were only produced when solutions containing calcium nitrate were used, suggesting that the charge of the Ca2+ ions had a significant effect. The resulting bioactive silica fibers had a narrow diameter range of 0.5–2 μm and were nanoporous. A hydroxycarbonate apatite layer was formed on the fibers within the first 12 h of soaking in simulated body fluid. MC3T3-E1 preosteoblast cells cultured on the fibers showed no adverse cytotoxic effect and they were observed to attach to and spread in the material.

Details

Original languageEnglish
Pages (from-to)3733-3746
Number of pages14
JournalActa Biomaterialia
Volume10
Issue number8
Early online date27 May 2014
Publication statusPublished - 1 Aug 2014

Keywords

  • electrospinning, Sol-gel, bone regeneration scaffold, 3-D cotton-wool-like structure, inorganic fibers