NANOTECHNOLOGY AND 3D BIOPRINTING FOR NEURAL TISSUE REGENERATION - 3D Bioprinting and Nanotechnology in Tissue Engineering and Regenerative Medicine - page 306

14.2.2 CARBON NANOBIOMATERIALS
The unique and versatile properties of carbon nanobiomaterials, including excellent electrical, thermal,
and mechanical properties, have led to greater research interest. A variety of carbon nanotubes/nanofibers
(CNTs/CNFs), and graphene nanomaterials ( Tran et al., 2009; Wang et al., 2011b ) have attracted
considerable attention for use as novel conductive scaffold materials for neural tissue regeneration.
Graphene is a carbon sheet measuring one atom in thickness composed of sp 2 -bonded carbon
atoms condensed in a hexagonal 2D lattice ( Fuhrer et al., 2010; Katsnelson, 2007 ). Due to this unique
structure, it is the thinnest and strongest material known ( Geim, 2009 ). As a basic building block of
all graphitic forms, graphene can be wrapped into 0D fullerenes, rolled into 1D carbon nanotubes, and
stacked into 3D graphite ( Geim and Novoselov, 2007; Rao et al., 2009 ) ( Figure 14.5 ). The unique
physical and chemical properties of graphene and graphene-based nanomaterials, such as high planar
surface area, electronic flexibility, superlative mechanical strength, and unparalleled thermal conduc-
tivity have increased their use in biological applications ( Yang et al., 2013a ). Graphene, graphene
oxide, chemically modified grapheme, and other graphene derivatives are some of the more popular
candidates for biomedical applications ( Wang et al., 2011b ). With regards to biocompatibility, recently
Park et al. studied nerve cell growth on the surface of graphene showing comparable cell viability
when compared to a polystyrene surface ( Park et al., 2013a ). Furthermore, Tang et al. investigated the
formation and performance of neural networks on graphene films ( Tang et al., 2013 ). It was demon-
strated that graphene has the capacity to improve nerve cell performance, and promote the growth and
facilitate electrical signaling of neural circuits. Such studies revealed the potential of graphene as an
FIGURE 14.5
Graphene forms: fullerenes, carbon nanotubes, and graphite. Images are adopted from Geim and Novoselov (2007) .