Biology Reference
In-Depth Information
Viral components hold great potential for nanotechnology because
viruses, due to their genome size and lifecycle restrictions, are typi-
cally required to assemble functional structures efficiently from a lim-
ited number of components, following a comparatively simple
construction plan.
2,3,5,61
The size of viruses is between tens to hun-
dreds of nanometers. This range falls into the dimension that is the
focus of study in nanotechnology. Viruses contain a wide variety of
nanomachines and ordered structures,
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including motors,
47,63-69
arrays,
70-73
pentons, and hexons. The novelty and ingenious design of
viral particles and structural components have long inspired the devel-
opment of biomimetics for nanodevices.
56,59
Structural components
and intermediates of assembly in viruses are exciting building blocks
in nanotechnological and bionanotechnological applications. One of
the current hot topics in viral research is to make these machines as
viable and effective as possible outside infectious viral particles.
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The
application of these structures and their derivatives includes the detec-
tion of pathogens, the delivery of drugs,
75
and the therapy and diag-
nosis of diseases.
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Additional applications include the gearing of
other nanodevices; the driving of molecular sorters; the building of
intricate arrays and chips; and the operation of new electronic and
optical devices,
77
including nanoelectromechanical systems (NEMS)
78
and molecular sensors or complex actuators.
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In general, viral structures are typically formed by multimers of
gene products. In order to apply such viral structures in nanotechnol-
ogy, knowledge of the stoichiometry of biological components is essen-
tial. Many physical and optical approaches have been successfully used
in viral stoichiometry quantification, including the use of STEM.
80-83
Readers are referred to these excellent review articles for detail.
Although many successful cases have been reported in the use of these
techniques for stoichiometry determination, direct quantification of
viral components and nanoparticles has been tedious and limited in
many cases. Since biological materials are often too soft and too small
for atomic force microscopy, it has been difficult to yield sufficient
resolution in negatively stained preparations, and to provide enough
contrast in (cryo) electron microscopy due to low electron density,
especially for nucleic acids.
