Playing “Nano -Lego ”: VNPs as Building Blocks for the Construction of Multi -Dimensional Arrays - Viral Nanoparticles: Tools for Materials Science and Biomedicine - page 194

Lvov ., 2005, 2006). Figure

7.20 depicts a multi-layered structure of CPMV particles and the polymer
pair linear poly(ethyleneimine) (PEI) and poly(acrylic acid) (PAA). CPMV
particles have a negative surface charge (under the conditions employed)
and bind stably to the positively charged PEI. An alternating structure of
polyelectrolyte with incorporated CPMV nanoparticles was self-assembled
(Steinmetz

et al ., 1994; Steinmetz et al ., 2008b; Suci et al

et al ., 2008b).

Figure 7.20 Scanning electron micrographs showing the sequential build-up of

polyelectrolytes and cowpea mosaic virus (CPMV) particles. (a) Precursor thin
film consisting of 2.5 bilayers of the polyions linear poly(ethyleneimine) (PEI) and
poly(acrylic acid) (PAA); (b) (PEI-PAA) CPMV; (c) (PEI-PAA) CPMV (PEIPAA); (d)

2.5 2.5

(PEI-PAA) CPMV; (f ) schematic

representation of the architecture. All images were viewed at an acceleration voltage of
5 kV with a Zeiss Supra 55 VP FEG SEM; scale bar: 1

CPMV (PEI-PAA) ; (e) (PEI-PAA) CPMV (PEI-PAA)

2.5 3 2.5 3

µ

m. Reproduced with permission
from Steinmetz, N. F., Findlay, K. C., Noel, T. R., Parker, R., Lomonossoff, G. P., and Evans,
D. J. (2008) Layer-by-layer assembly of viral nanoparticles and polyelectrolytes:
the film architecture is different for spheres versus rods, ChemBioChem , 9 (10),

1662-1670.