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P. Madiwale et al.
6.1.2 Various Forms of Silk Protein and Their Applicability in Tissue
Scaffolds
Indigenous Fibres
The raw silk obtained in the form of fibres from the silk worm is degummed and
can be used in tissue engineering in various forms such as rope, cable, textured
yarn and braided fabric. A non-woven structure can be formed using silk cocoon
by dissolving them partially to use as a cell supporting template. In this type of
structure arrangement of filaments is maintained to impart porosity in nonwoven
structure, which is an important requirement of tissue engineering scaffold. A knitted
silk structure to reinforce 3-D porous tissue engineering scaffolds can also be used
in ligament which is a load bearing tissue.
Regenerated Silk
Concentrated solution of various salts like LiBr, CaCL 2 /ethanol/water, LiSCN or
ionic liquids have been used as solvent to dissolve silk to prepare different form of
regenerated silk protein available for engineering tissue for different applications.
Films
Films from silk fibrion can be prepared by casting the silk solution obtained by
dissolving the protein. To improve β-sheet crystallinity, different techniques such
as controlled drying, water annealing, and alcohol immersion are used and thus to
increase the water stability of the regenerated films. Surface properties required for
tissue engineering applications can be obtained by using lithography and advanced
printing systems.
Electro-Spun and Wet-Spun Fibers
The regenerated silk solution is used for spinning the nano fibres mats using electrospinning. These mats are utilised for cell seeding or as 3-D constructs in grafting
of blood vessels and nerve guides. The regenerated silk fibres having micrometer
scale can be produced with higher production rate than nano-fibers by employing
spinning using solvent spinning or micro-fluidic solution spinning. Regeneration of
fibers enables tuning of fiber morphology and subsequently application focussed
properties. Bio-molecules can also be incorporated during spinning [29].
P. Madiwale et al.
6.1.2 Various Forms of Silk Protein and Their Applicability in Tissue
Scaffolds
Indigenous Fibres
The raw silk obtained in the form of fibres from the silk worm is degummed and
can be used in tissue engineering in various forms such as rope, cable, textured
yarn and braided fabric. A non-woven structure can be formed using silk cocoon
by dissolving them partially to use as a cell supporting template. In this type of
structure arrangement of filaments is maintained to impart porosity in nonwoven
structure, which is an important requirement of tissue engineering scaffold. A knitted
silk structure to reinforce 3-D porous tissue engineering scaffolds can also be used
in ligament which is a load bearing tissue.
Regenerated Silk
Concentrated solution of various salts like LiBr, CaCL 2 /ethanol/water, LiSCN or
ionic liquids have been used as solvent to dissolve silk to prepare different form of
regenerated silk protein available for engineering tissue for different applications.
Films
Films from silk fibrion can be prepared by casting the silk solution obtained by
dissolving the protein. To improve β-sheet crystallinity, different techniques such
as controlled drying, water annealing, and alcohol immersion are used and thus to
increase the water stability of the regenerated films. Surface properties required for
tissue engineering applications can be obtained by using lithography and advanced
printing systems.
Electro-Spun and Wet-Spun Fibers
The regenerated silk solution is used for spinning the nano fibres mats using electrospinning. These mats are utilised for cell seeding or as 3-D constructs in grafting
of blood vessels and nerve guides. The regenerated silk fibres having micrometer
scale can be produced with higher production rate than nano-fibers by employing
spinning using solvent spinning or micro-fluidic solution spinning. Regeneration of
fibers enables tuning of fiber morphology and subsequently application focussed
properties. Bio-molecules can also be incorporated during spinning [29].