Chemistry Reference
In-Depth Information
Fig. 17 Assembly of the
SWCNT electrically-
contacted glucose oxidase
electrode. SWCNT was firstly
immobilized via
carbodiimide chemistry on
the electrode surface, and
then the amino derivative of
the flavin adenine
dinucleotide (FAD) cofactor
was covalently attached to the
carboxyl groups at the
SWCNT tips [
62
]
the alcohol nucleophilic substitution by previous reaction with an acyl chloride.
The literature offers a wide range of examples along this line, describing CNTs
variously conjugated with porphyrins, lipophilic and hydrophilic dendrons, polyols,
etc. [
70
-
73
].
The formation of carbon nanotube-inorganic hybrids using this approach have
been widely explored and gives rise to a new strategy for building metallo-
nanomaterials, which could find potential applications in nanoscale electronic
devices [
74
,
75
] (Fig.
18
).
Au dendrimer encapsulated nanoparticles (DENs) have also been immobilized
onto the surface of MWCNTs functionalized with carboxylic acid groups. This
acidic functionalization leads to debundling of MWCNTs and provides surface sites
for interactions with amino groups present on the surface of the dendrimer [
76
]
(Fig.
19
).
4.1.2 Covalent Sidewall Chemistry
In contrast to the esterification or amidation reaction of the acid groups in oxidized
CNTs, the functionalization via direct reactions is more difficult to accomplish
