Development of a Novel Ion Eluting Copolymer Network for Osteogenic Applications

UoM administered thesis: Phd

  • Authors:
  • Tianhao Zhou

Abstract

The current clinical treatment for bone deficiencies in clinics includes autografts, allografts and bone graft substitutes. All these treatments, however, still have various limitations. Therefore, in this project, we aim to design, synthesise and characterise a new series of novel polymer networks (PNs) to promote bone formation and offer a new therapeutic solution. An innovative polymerisation technique was used to synthesise the novel polymer-based materials. Various lactone monomers were applied with layered double hydroxides (LDHs) as the initiator for the polymerisation. Copolymerisation was used to control the final product degradation rate, microstructure and biocompatibility. SEM and XRD were used to confirm the formation of the 3D polymer microstructure, PNs indicated interconnected fibrous microstructure (thickness of the fibre ranged from 50-150 nm). Up to 90% polymer yield was achieved using thermogravimetric analysis. Both 1H and 13C nuclear magnetic resonance (NMR) were used to understand the effects of monomer combinations in the polymerisation. The effects of the materials on osteosarcoma cell line Saos-2 were investigated. Representative material compositions and their determined mass concentrations were applied using osteogenic culture medium with Saos-2. The PNs have indicated enhanced osteogenesis using varied assays. A poly(lactide-co-caprolactone) PN (monomer mass ratio 1:1) at 6.25 mg/ml, in particular, resulted in enhanced alkaline phosphate activity not only in growth medium but also in osteogenic medium. Moreover, it indicated the highest bone nodule production in area percentage compared to the other PN samples using Saos-2. Mg-substituted calcified extracellular matrix was formed by the use of PN materials. Therefore, this novel PN could have the possibility to be used as an acellular scaffold or a sprinkle-on powder local to defect site to enhance bone formation in vivo. In addition, this novel technology could be used as a scaffold for tissue engineering.

Details

Original languageEnglish
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Supervisors/Advisors
Award date31 Dec 2018