Fabrication of tissue engineering scaffolds using the emulsion freezing/freeze-drying technique and characteristics of the scaffolds

Published on Apr 4, 2012
· DOI :10.1002/9781118371183.CH4
Naznin Sultana18
Estimated H-index: 18
(HKU: University of Hong Kong),
Min Wang79
Estimated H-index: 79
(HKU: University of Hong Kong)
Sources
Abstract
Polyhydroxybutyrate (PHB) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) are natural and biodegradable polymers and have attracted much attention for their application as materials for tissue engineering scaffolds. In the current study, the emulsion freezing/freeze-drying technique was investigated for fabricating mainly PHBV-based scaffolds. The scaffolds included pure polymer scaffolds, polymer blend scaffolds and nanocomposite scaffolds. The influence of various processing parameters in the emulsion freezing/freeze-drying process was studied and good-quality, highly porous scaffolds could be produced. The characteristics of scaffolds were studied using various techniques. All scaffolds could have three-dimensional porous structures with high interconnectivity, and pore sizes ranged from several microns to a few hundred microns. Under compression, all scaffolds exhibited typical mechanical behavior of cellular solids. The incorporation of nanosized bioceramic particles stiffened scaffolds. Furthermore, the nanocomposite scaffolds enhanced osteoblastic cell attachment, proliferation, and differentiation. With the formation of a thin collagen coating on pore surfaces of PHBV-based scaffolds, the biological performance of the scaffolds was significantly improved.
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