An Introduction to VNPs and Nanotechnology - Viral Nanoparticles: Tools for Materials Science and Biomedicine - page 2

of 100 µm and are thus 10 times smaller than the aphid and still 100,000
times bigger than a nanoparticle. Panel C shows a plant cell, which is about
10 µm in size and thus 10,000 bigger than a nanometer. Particles formed by
the plant virus (CPMV; Fig. 1.1, panel D) are about 30

nm in diameter and thus nanoparticles. One would need around 50,000,000
VNPs to fill up the interior of a cell.
A single atom is a fraction of a nanometer in size; molecules, including
biological molecules, are typically nanometers in size and can thus be
regarded as nanoobjects. In recent years a range of biological molecules
have been exploited for nanosciences and nanotechnology. Nucleic acids,
for example, are used as construction materials to generate highly ordered
2D and 3D structures and assemblies such as nanotubes and nanocages.
A main theme in nanotechnology is controlled self-assembly, with the goal
being to generate functional materials with a high degree of precision.
Nanotechnology, then, requires chemical and physical control at the molecular
level. Nucleic acids, proteins, and viruses are essentially naturally occurring
nanomaterials capable of self-assembly with a high degree of precision.
This property, coupled to the relative ease of experimentally controlling
and producing biological nanomaterials, has led to tremendous interest in
their nanotechnology applications. Viruses, and VNPs in particular, possess a
number of traits that make them exceptionally outstanding candidates.

Cowpea mosaic virus

Figure 1.1 Scanning electron micrographs of aphids on leaf (A), human hair (B),

fractured plant cell (C), and

particles (D). Panel A-C provided by
courtesy of Kim C. Findlay, John Innes Centre, Norwich (UK). Panel D from Steinmetz,
N. F., et

Cowpea mosaic virus

al. , unpublished.