Multifunctional 45S5 Bioglass® - based composite scaffolds for bone tissue engineering
File(s)
Author(s)
Newby, Phillipa Jane
Type
Thesis
Abstract
In the evolving field of bone tissue engineering, bioactive glass-ceramic scaffolds continue to draw significant attention as they can provide a 3D template that promotes new bone formation. These scaffolds have proved that they can loosely mimic cancellous bone structure as well as exhibiting appropriate mechanical properties and bioactivity to support the growth of new bone tissue.
This work concentrates on improving the functionality of 45S5 Bioglass® -derived scaffolds produced by the foam replication technique, by introducing silver and copper through molten salt ion exchange to provide an antibacterial function and through the use of gelatin coatings to improve compressional strength, whilst not impeding the original scaffold’s bioactivity.
The results confirmed that the introduced modifications have enhanced the scaffolds functionality as well as improving existing properties of the scaffolds such as mechanical competence. Overall the compressive strength of the scaffolds was improved with the addition of copper and silver ions and by the presence of gelatin coatings. After immersion in SBF, the presence of the additives did not impede the formation of hydroxyapatite on the scaffolds and hence the bioactivity. The characterization of the doped and coated samples showed that they have similar behavior to those of the base scaffold or have improved them marginally in terms of wettability and surface topography.
During cell culture studies, using HPLSC’s, rMSC’s and hMSC’s, the silver doped scaffolds caused a slight cytotoxic effect, whilst the copper and silver/copper samples caused a significant cytotoxic effect. Bacterial studies showed that the metal ion-doped materials produced an antibacterial effect against the E.coli, S.aureus and K.pneumoniae. The present study has contributed to the enhancement of the standard 45S5 Bioglass® -derived scaffolds and has provided a base for future in vitro and in vivo work involving these materials in bone regeneration strategies.
This work concentrates on improving the functionality of 45S5 Bioglass® -derived scaffolds produced by the foam replication technique, by introducing silver and copper through molten salt ion exchange to provide an antibacterial function and through the use of gelatin coatings to improve compressional strength, whilst not impeding the original scaffold’s bioactivity.
The results confirmed that the introduced modifications have enhanced the scaffolds functionality as well as improving existing properties of the scaffolds such as mechanical competence. Overall the compressive strength of the scaffolds was improved with the addition of copper and silver ions and by the presence of gelatin coatings. After immersion in SBF, the presence of the additives did not impede the formation of hydroxyapatite on the scaffolds and hence the bioactivity. The characterization of the doped and coated samples showed that they have similar behavior to those of the base scaffold or have improved them marginally in terms of wettability and surface topography.
During cell culture studies, using HPLSC’s, rMSC’s and hMSC’s, the silver doped scaffolds caused a slight cytotoxic effect, whilst the copper and silver/copper samples caused a significant cytotoxic effect. Bacterial studies showed that the metal ion-doped materials produced an antibacterial effect against the E.coli, S.aureus and K.pneumoniae. The present study has contributed to the enhancement of the standard 45S5 Bioglass® -derived scaffolds and has provided a base for future in vitro and in vivo work involving these materials in bone regeneration strategies.
Version
Open Access
Date Issued
2013-11
Date Awarded
2014-11
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Boccaccini, Aldo
Saiz, Eduardo
Sponsor
Engineering and Physical Sciences Research Council
Publisher Department
Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)