Playing “Nano -Lego ”: VNPs as Building Blocks for the Construction of Multi -Dimensional Arrays - Viral Nanoparticles: Tools for Materials Science and Biomedicine - page 177

As mentioned above, liquid crystalline films of hybrid mineralized M13
particles can also be constructed (Lee ., 2002, 2003a). To this end, a

phage was engineered that expresses a streptavidin-binding peptide at the
terminal pIII protein. The streptavidin-binding peptide provides a unique
handle that allows picking up of any material that has been covalently
conjugated to streptavidin. In a proof-of-concept experiment, materials such
as gold, fluorescein, or phycoerythrin were “picked up” with the phage and
then assembled into a liquid crystalline structure (Lee

et al

., 2003a).
Like M13, TMV also shows liquid crystalline behavior. Convective
assembly methods have been used to deposit thin films of highly ordered
TMV particles onto surfaces (Fig. 7.7) (Kuncicky

et al

.,
2008). Convective methods are inexpensive, simple, reliable, and versatile.
Films in the centimeter size range can be fabricated. It was found that best
ordering is achieved on hydrophilic substrates. The film structure and degree

et al ., 2006; Wargacki et al

Figure 7.7 (a) Schematic representation of the apparatus for depositing aligned

virus-fiber coatings. Typically, virus suspension (20 ml) was entrained between
two glass plates held at a fixed angle. The entrained meniscus was dragged across
the substrate, and aligned fibers were deposited across the entire surface of the
2.5 × 7.5 cm substrate. (b) Bright-field image of a freely receding meniscus showing

shear-induced alignment in suspension near the three-phase contact line. (c) Phase-
contrast optical image of the receding contact line showing TMV-fiber formation on
a hydrophobic substrate. Scanning electron microscopic (SEM) image of (d) 5 mg/
ml and (e) 40 mg/ml TMV deposited on hydrophilic substrates. Inset: tapping-mode
atomic force microscopic (AFM) image of an individual fiber from (e). The scale
bars in (b-e) are 500, 100, 5, and 5 mm, respectively, and the scale bar for the inset
represents 250 nm. Reproduced with permission from Kuncicky, D. M., Naik, R. R.,
and Velev, O. D. (2006) Rapid deposition and long-range alignment of nanocoatings
and arrays of electrically conductive wires from tobacco mosaic virus,

2

Small , 2 (12),

1462-1466.