Physics And Chemistry Basis Of Biotechnology - De Cuyper - tiera.ru

Aleksey Nedoluzhko and Trevor Douglas
trioctylphosphine oxide and tributylphosphine oxide had interparticle distances of 17,
1 1, and 7 Å respectively.
Figure 19 Aggregation of biotinylated ferritin containing iron oxide particles in the
presence of streptavidin Reprinted by permission from Chem Mater [I47] Copyright
1999 ACS Publications
Certain organic molecules may be employed to form organised nanoparticle arrays
through covalent linking of the particles. This technique was demonstrated, for
example, for the synthesis of two-dimensional arrays of 3.7 nm gold particles linked by
an aryl di-isonitrile (1,4-di(4-isocyanophenylethynyl)-2-ethylbenzene) [145],
More biological approach to the nanoparticle assembly uses highly specific
interactions between certain biomolecules. Besides nucleotide-nucleotide interactions,
two other biological recognition systems were used to assemble inorganic
nanoparticles. In the study of Shenton et al. [146] 12 nm Au and Ag nanoparticles with
attached either IgE or IgG antibodies formed arrays in the presence of bivalent antigens
with two appropriate functionalities. Filaments consisting of closely packed metal
particles were observed. The other strategy uses streptavidin – biotin interaction. This is
of particular interest because of the large association energy of the complex. In the
presence of streptavidin the assembly of biotinylated ferritin shells with inorganic cores
was demonstrated [147] (Figure 19). Streptavidin was also shown to promote
aggregation of gold nanoparticles modified with a disulfide biotin analogue [ 148].
Most of the above-mentioned methods employ specific organic-organic
interactions. A more direct approach to nanoparticle assembly involves specific
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