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Title: Freeze casting of porous hydroxyapatite scaffolds – I. Processing and general microstructure
Author (s): Fu, Qiang
Rahaman, Mohamed
Dogan, Fatih
Bal, B. Sonny
Department/Lab Affiliations: Energy Research and Development Center
Materials Research Center
Materials Science & Engineering
University Transportation Center
Virtual Reality & Rapid Prototyping Lab
Keywords: biomaterials
freeze casting
hydroxyapatite
porous ceramics
scaffolds
Issue Date: 2007-12-20
Publisher: John Wiley & Sons
Citation: Fu, Qiang., Rahaman, Mohamed N., Dogan, Fatih., and Bal, B. Sonny. "Freeze Casting of Porous Hydroxyapatite Scaffolds – I. Processing and General Microstructure.", Journal of Biomedical Materials Research Part B: Applied Biomaterials, vol. 86B, no. 1, 2007.
Abstract: Freeze casting of aqueous suspensions on a cold substrate was investigated as a method for preparing hydroxyapatite (HA) scaffolds with unidirectional porosity. In the present paper, we report on the ability to manipulate the microstructure of freeze-cast constructs by controlling the processing parameters. Constructs prepared from aqueous suspensions (5-20 volume percent particles) on a steel substrate at -20°C had a lamellar-type microstructure, consisting of plate-like HA and unidirectional pores oriented in the direction of freezing. Sintering for 3 h at 1350°C produced constructs with dense HA lamellas, porosity of 50%, and inter-lamellar pore widths of 5-30 m. The thickness of the HA lamellas decreased but the width of the pores increased with decreasing particle concentration. Decreasing the substrate temperature from -20°C to -196°C produced a finer lamellar microstructure. The use of water-glycerol mixtures (20 wt % glycerol) as the solvent in the suspension resulted in the production of finer pores (1-10 m) and a larger number of dendritic growth connecting the HA lamellas. On the other hand, the use of water-dioxane mixtures (60 wt % dioxane) produced a cellular-type microstructure with larger pores (90-110 m). The ability to produce a uniaxial microstructure and its manipulation by controlling the processing parameters indicate the potential of the present freeze casting route for the production of scaffolds for bone tissue engineering applications.
Type: Article - Journal
text
In Title: Journal of Biomedical Materials Research Part B: Applied Biomaterials
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http://www.wiley.com/WileyCDA/Section/id-301854.html
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Publisher URL:
http://dx.doi.org/10.1002/jbm.b.30997
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titleFreeze casting of porous hydroxyapatite scaffolds – I. Processing and general microstructure
contributor.authorFu, Qiang
contributor.authorRahaman, Mohamed
contributor.authorDogan, Fatih
contributor.authorBal, B. Sonny
contributor.deptlabEnergy Research and Development Center
contributor.deptlabMaterials Research Center
contributor.deptlabMaterials Science & Engineering
contributor.deptlabUniversity Transportation Center
contributor.deptlabVirtual Reality & Rapid Prototyping Lab
subjectbiomaterials
subjectfreeze casting
subjecthydroxyapatite
subjectporous ceramics
subjectscaffolds
date.issued2007-12-20
publisherJohn Wiley & Sons
identifier.citationFu, Qiang., Rahaman, Mohamed N., Dogan, Fatih., and Bal, B. Sonny. "Freeze Casting of Porous Hydroxyapatite Scaffolds – I. Processing and General Microstructure.", Journal of Biomedical Materials Research Part B: Applied Biomaterials, vol. 86B, no. 1, 2007.
identifier.pub.URI
http://dx.doi.org/10.1002/jbm.b.30997
description.abstractFreeze casting of aqueous suspensions on a cold substrate was investigated as a method for preparing hydroxyapatite (HA) scaffolds with unidirectional porosity. In the present paper, we report on the ability to manipulate the microstructure of freeze-cast constructs by controlling the processing parameters. Constructs prepared from aqueous suspensions (5-20 volume percent particles) on a steel substrate at -20°C had a lamellar-type microstructure, consisting of plate-like HA and unidirectional pores oriented in the direction of freezing. Sintering for 3 h at 1350°C produced constructs with dense HA lamellas, porosity of 50%, and inter-lamellar pore widths of 5-30 m. The thickness of the HA lamellas decreased but the width of the pores increased with decreasing particle concentration. Decreasing the substrate temperature from -20°C to -196°C produced a finer lamellar microstructure. The use of water-glycerol mixtures (20 wt % glycerol) as the solvent in the suspension resulted in the production of finer pores (1-10 m) and a larger number of dendritic growth connecting the HA lamellas. On the other hand, the use of water-dioxane mixtures (60 wt % dioxane) produced a cellular-type microstructure with larger pores (90-110 m). The ability to produce a uniaxial microstructure and its manipulation by controlling the processing parameters indicate the potential of the present freeze casting route for the production of scaffolds for bone tissue engineering applications.
typeArticle - Journal
type.DCMITypetext
rightsThis material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.
rightsPre-print: author can archive; Post-print: author can archive;
rights.URI
http://www.wiley.com/WileyCDA/Section/id-301854.html
rights.URI
http://www3.interscience.wiley.com/homepages/central/cta/UKscta.pdf
relation.isPartOfJournal of Biomedical Materials Research Part B: Applied Biomaterials
date.available2008-08-06T21:21:22Z
identifier.persist.URI
http://scholarsmine.mst.edu/post_prints/FreezeCastingOfPorousHydroxyapatiteScaffolds-I_09007dcc8054bdd2.html