Fabrication of Nanostructured Scaffolds …
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ii. Drug Delivery—controlled drug delivery incorporated drug or bioactive
molecules can be effectively delivered from nanostructured materials by
degradation or diffusion mechanism.
iii. Scaffolds –used to support improved cell adhesion, proliferation with larger
surface area, and porous nature with interconnected pores, biocompatibility,
and biodegradability.
iv. Wound Healing—novel wound healing scaffolds developed with various
biopolymers and active compounds for enhanced tissue healing.
Several in vitro studies of nanofibrous wound healing bandages, scaffolds and drug
delivery carriers have shown that nanostructured materials outperform their micro or
macro architecture scaffold counterparts with similar material composition. Hence,
nanofibrous assemblies can be tailor-made to distinct tissue engineering applications.
5 Nanostructured Scaffolds for Tissue and Bone
Regeneration Applications
The tissue engineering market is valued at around USD 5 billion in 2016 and is
expected to grow at a healthy rate. According to the Centers for Medicare and Medicaid, more than 900,000 surgeries are performed each year in the United States for
bone reconstruction or replacement. Currently, nanotechnology-based products are
few and are only available for tissue regeneration such as Acticoat
TM Flex 3 and 7
(Smith & Nephew., UK) nano silver-containing wound dressing, Polymem
® silver
(Ferris Mfg. Corp., USA) and Regrenex
® gel (Smith & Nephew., UK) [21]. When
compared to topical application, scaffolds developed in nanostructured architecture
potentially mimic the ECM structure. Currently, electrospinning technology widely
used to fabricate nanofibrous scaffolds with improved cell adhesion and proliferation
for wound healing and bone tissue regeneration applications.
6 Need for Biodegradable Materials
The scaffolds developed for drug delivery and tissue engineering applications need
to be biocompatible and biodegradable [22]. The degradability rate must be equal to
the healing rate of the tissue. Biocompatibility is an additional key feature for any
scaffold used for tissue engineering applications, which should be devoid of toxicity,
favor cell adhesion and proliferation, allow the exchange of gas and nutrients from
the blood, and provide adequate mechanical strength [23]. The biomaterials used
for tissue engineering include polymers, ceramics, composites, metals, and alloys
[24]. These different classes of biomaterials were shown in Fig. 3. The degradation
rate of a tissue-engineered scaffold is controlled and gradual, which leads to the
transfer of the mechanical load to the surrounding tissue and bone, which avoids the
321
ii. Drug Delivery—controlled drug delivery incorporated drug or bioactive
molecules can be effectively delivered from nanostructured materials by
degradation or diffusion mechanism.
iii. Scaffolds –used to support improved cell adhesion, proliferation with larger
surface area, and porous nature with interconnected pores, biocompatibility,
and biodegradability.
iv. Wound Healing—novel wound healing scaffolds developed with various
biopolymers and active compounds for enhanced tissue healing.
Several in vitro studies of nanofibrous wound healing bandages, scaffolds and drug
delivery carriers have shown that nanostructured materials outperform their micro or
macro architecture scaffold counterparts with similar material composition. Hence,
nanofibrous assemblies can be tailor-made to distinct tissue engineering applications.
5 Nanostructured Scaffolds for Tissue and Bone
Regeneration Applications
The tissue engineering market is valued at around USD 5 billion in 2016 and is
expected to grow at a healthy rate. According to the Centers for Medicare and Medicaid, more than 900,000 surgeries are performed each year in the United States for
bone reconstruction or replacement. Currently, nanotechnology-based products are
few and are only available for tissue regeneration such as Acticoat
TM Flex 3 and 7
(Smith & Nephew., UK) nano silver-containing wound dressing, Polymem
® silver
(Ferris Mfg. Corp., USA) and Regrenex
® gel (Smith & Nephew., UK) [21]. When
compared to topical application, scaffolds developed in nanostructured architecture
potentially mimic the ECM structure. Currently, electrospinning technology widely
used to fabricate nanofibrous scaffolds with improved cell adhesion and proliferation
for wound healing and bone tissue regeneration applications.
6 Need for Biodegradable Materials
The scaffolds developed for drug delivery and tissue engineering applications need
to be biocompatible and biodegradable [22]. The degradability rate must be equal to
the healing rate of the tissue. Biocompatibility is an additional key feature for any
scaffold used for tissue engineering applications, which should be devoid of toxicity,
favor cell adhesion and proliferation, allow the exchange of gas and nutrients from
the blood, and provide adequate mechanical strength [23]. The biomaterials used
for tissue engineering include polymers, ceramics, composites, metals, and alloys
[24]. These different classes of biomaterials were shown in Fig. 3. The degradation
rate of a tissue-engineered scaffold is controlled and gradual, which leads to the
transfer of the mechanical load to the surrounding tissue and bone, which avoids the