Advances of Textiles in Tissue Engineering Scaffolds
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their fibre covering such as sheepskins. Wool fibres is composed of the animal protein
such as keratin with molecular weight ranging from 45 to 60 KDa of the micro-fibrils
from the cortical cells to 6–28 kDa of the protein from the matrix [36].
The application of keratin in the field of tissue engineering has been late boosted
due to its limited water solubility and the number of methods available for its extraction and processing. It did not gain the momentum as tissue scaffold as that of other
biomaterials. However, in last ten years, due to the development in the extraction
and application methods, keratin or modified keratin has emerged as one of most
valuable biomaterial or scaffold in the field of cell cultivation and tissue engineering
[10].
Keratin occupies about 50% by weight of the cortical cells (outer layer of wool).
Compared to other proteins, keratin is abundantly available with less extraction cost.
The inherent properties of wool keratin such as highly conserved superstructure,
intrinsic ability to self-assemble and polymerize into porous fibrous scaffolds are
extremely efficient for the reproducible architecture, dimensionality and porosity of
keratin-based materials.
In comparison with other bio-materials, keratin biomaterials possess many distinct advantages, including a unique chemistry yielded by their high sulphur content,
excellent biocompatibility, propensity for self-assembly, and intrinsic cellular recognition. The wool keratin as bio-material is researched in various forms and described
in the following sections for its application as tissue scaffolds [37].
6.2.1 Keratin Films
The structural and biological properties of keratin protein film extracted from wool
have been explored for last few years. The major limitations are flexibility and
strength of the films. Addition of natural and synthetic polymers to keratin blended
systems like chitosan, silk fibroin, poly-(hydroxyl butylate co-hydroxy valerate),
polyethylene oxide, polyvinyl alcohol, gelatin are researched for the enhancing the
properties of keratin films. Different techniques other than solvent casting such as
compression moulding and substrate coating are employed for preparation of keratin
and keratin blended films.
6.2.2 Keratin Sponges
The extracted keratin is lyophilized to form porous sponges which can be applied
as support for tissue growth. The wool keratin which contains Arginine-glycineaspartate protein sequence which are favourable for cell adhesion and promote healing thus increase in cell compatibility, attachment and proliferation of cells. The
keratin protein is also used by modifying the protein with various chemical treatments. The research is been carried out to functionalise the sponges using iodoacetic
acid, 2-bromoethylamine, and iodoacetamide to produce carboxyl-, amino-, and
amido-sponges, respectively.
179
their fibre covering such as sheepskins. Wool fibres is composed of the animal protein
such as keratin with molecular weight ranging from 45 to 60 KDa of the micro-fibrils
from the cortical cells to 6–28 kDa of the protein from the matrix [36].
The application of keratin in the field of tissue engineering has been late boosted
due to its limited water solubility and the number of methods available for its extraction and processing. It did not gain the momentum as tissue scaffold as that of other
biomaterials. However, in last ten years, due to the development in the extraction
and application methods, keratin or modified keratin has emerged as one of most
valuable biomaterial or scaffold in the field of cell cultivation and tissue engineering
[10].
Keratin occupies about 50% by weight of the cortical cells (outer layer of wool).
Compared to other proteins, keratin is abundantly available with less extraction cost.
The inherent properties of wool keratin such as highly conserved superstructure,
intrinsic ability to self-assemble and polymerize into porous fibrous scaffolds are
extremely efficient for the reproducible architecture, dimensionality and porosity of
keratin-based materials.
In comparison with other bio-materials, keratin biomaterials possess many distinct advantages, including a unique chemistry yielded by their high sulphur content,
excellent biocompatibility, propensity for self-assembly, and intrinsic cellular recognition. The wool keratin as bio-material is researched in various forms and described
in the following sections for its application as tissue scaffolds [37].
6.2.1 Keratin Films
The structural and biological properties of keratin protein film extracted from wool
have been explored for last few years. The major limitations are flexibility and
strength of the films. Addition of natural and synthetic polymers to keratin blended
systems like chitosan, silk fibroin, poly-(hydroxyl butylate co-hydroxy valerate),
polyethylene oxide, polyvinyl alcohol, gelatin are researched for the enhancing the
properties of keratin films. Different techniques other than solvent casting such as
compression moulding and substrate coating are employed for preparation of keratin
and keratin blended films.
6.2.2 Keratin Sponges
The extracted keratin is lyophilized to form porous sponges which can be applied
as support for tissue growth. The wool keratin which contains Arginine-glycineaspartate protein sequence which are favourable for cell adhesion and promote healing thus increase in cell compatibility, attachment and proliferation of cells. The
keratin protein is also used by modifying the protein with various chemical treatments. The research is been carried out to functionalise the sponges using iodoacetic
acid, 2-bromoethylamine, and iodoacetamide to produce carboxyl-, amino-, and
amido-sponges, respectively.