Several researchers have also used alginate to create hybrid biomaterials for
CTE. Bai et al. (2011) made alginate/collagen composite microbeads for EHT. The
3D porous composite scaffold formed from different ratio of alginate and chitosan
by freeze drying method showed significant increase in ejection fraction, improved
neo-vascularisation, attenuated fibrosis and proliferation of CMs (Ceccaldi et al.
2013). Mollar et al. developed hydrogel composites from methacrylated hyaluronic
acid, alginate and gelatin (Moller et al. 2011). The composite of alginate/elastin and
PEG showed large pore size (approx 60–75 µm) as compared to alginate and elastin
composite at 20 °C (Chandy et al. 2003). The larger pore size membranes retained
less water content and high degradation profile and hence, were suitable for CTE.
Sapir et al. also created a functional cardiac patch from rat cardiac cells seeded on
macroporous alginate scaffold incorporated with magnetically responsive
nanoparticles (MNPs) (Sapir et al. 2014b).
18.3.5 Chitosan
Chitosan, a natural cationic polysaccharide and linear polymer obtained from chitin
through deacetylation process and linked via b, 1–4 linkage, has also been found
suitable as for CTE (Hussain et al. 2013). The low mechanical strength of chitosan
scaffolds can be overcome by formation of composite materials and creation of
nanofibers (Albanna et al. 2012). Chitosan hydrogel, incorporated with glutathione,
suppressed reactive oxygen species (ROS) and showed high survival of CMs (Li
et al. 2013). Liu et al. (2012) reported that chitosan hydrogel can scavenge ROS
molecules and improve the environment for cell engraftment, survival and homing
for ischemic heart.
Chitosan is occasionally used as hybrid biomaterials along with other natural or
synthetic biomaterials. For example, copolymer of chitosan and poly(e-caprolactone)
(PCL) provided better cell adhesion and mechanical strength for development of
cardiac tissue construct than Chitosan or PCL alone (Chatzinikolaidou et al. 2014).
The multilayer scaffold prepared from combination of chitosan, gelatin and PCL was
also found to be suitable for CTE (Pok et al. 2013). Similarly, micro-patterned aligned
collagen-chitosan hydrogel enhanced the success rate of beating CMs, oxygen
transport and provided better cell connections with construct (Zhang et al. 2013). Baei
et al. (2016) developed a thermo-sensitive conductive hydrogel with a highly porous
network of interconnected pores by incorporating nanoscale electro-conductive gold
nanoparticles into chitosan hydrogels.
18.3.6 Fibroin/Silk Fibroin
Fiboin present as natural form in silkworms, moths, spiders, silverfish, beetles etc.
is also a good source of natural biomaterial for CTE. Silk from mulberry Bombyx
18 Cardiac Tissue Engineering: A Role for Natural Biomaterials
625
CTE. Bai et al. (2011) made alginate/collagen composite microbeads for EHT. The
3D porous composite scaffold formed from different ratio of alginate and chitosan
by freeze drying method showed significant increase in ejection fraction, improved
neo-vascularisation, attenuated fibrosis and proliferation of CMs (Ceccaldi et al.
2013). Mollar et al. developed hydrogel composites from methacrylated hyaluronic
acid, alginate and gelatin (Moller et al. 2011). The composite of alginate/elastin and
PEG showed large pore size (approx 60–75 µm) as compared to alginate and elastin
composite at 20 °C (Chandy et al. 2003). The larger pore size membranes retained
less water content and high degradation profile and hence, were suitable for CTE.
Sapir et al. also created a functional cardiac patch from rat cardiac cells seeded on
macroporous alginate scaffold incorporated with magnetically responsive
nanoparticles (MNPs) (Sapir et al. 2014b).
18.3.5 Chitosan
Chitosan, a natural cationic polysaccharide and linear polymer obtained from chitin
through deacetylation process and linked via b, 1–4 linkage, has also been found
suitable as for CTE (Hussain et al. 2013). The low mechanical strength of chitosan
scaffolds can be overcome by formation of composite materials and creation of
nanofibers (Albanna et al. 2012). Chitosan hydrogel, incorporated with glutathione,
suppressed reactive oxygen species (ROS) and showed high survival of CMs (Li
et al. 2013). Liu et al. (2012) reported that chitosan hydrogel can scavenge ROS
molecules and improve the environment for cell engraftment, survival and homing
for ischemic heart.
Chitosan is occasionally used as hybrid biomaterials along with other natural or
synthetic biomaterials. For example, copolymer of chitosan and poly(e-caprolactone)
(PCL) provided better cell adhesion and mechanical strength for development of
cardiac tissue construct than Chitosan or PCL alone (Chatzinikolaidou et al. 2014).
The multilayer scaffold prepared from combination of chitosan, gelatin and PCL was
also found to be suitable for CTE (Pok et al. 2013). Similarly, micro-patterned aligned
collagen-chitosan hydrogel enhanced the success rate of beating CMs, oxygen
transport and provided better cell connections with construct (Zhang et al. 2013). Baei
et al. (2016) developed a thermo-sensitive conductive hydrogel with a highly porous
network of interconnected pores by incorporating nanoscale electro-conductive gold
nanoparticles into chitosan hydrogels.
18.3.6 Fibroin/Silk Fibroin
Fiboin present as natural form in silkworms, moths, spiders, silverfish, beetles etc.
is also a good source of natural biomaterial for CTE. Silk from mulberry Bombyx
18 Cardiac Tissue Engineering: A Role for Natural Biomaterials
625