Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 4, pp. 661−665.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © S.V. Valueva, L.N. Borovikova, N.A. Matveeva, 2011, published in Zhurnal Prikladnoi Khimii, 2011, Vol. 84, No. 4, pp. 624−628.
AND POLYMERIC MATERIALS
Selenium-Containing Nanocomplexes Stabilized
by Various Types of Matrices:
a Study by UV–Visible Spectroscopy
S. V. Valueva, L. N. Borovikova, and N. A. Matveeva
Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
Received May 24, 2010
Abstract—Selenium-containing nanosystems based on nonionic polymers (polyvinylpyrrolidone, oxyethyl
cellulose), a cationic polyelectrolyte (poly-N,N,N,N-trimethylmethacryloyloxyethylammonium methyl sulfate), and
anionic polyelectrolytes (poly-2-acrylamido-2-methylpropanesulfonic and polymethacrylic acids) were studied.
Adsorption of organic additives on nanoparticles leads
to the formation of an organic shell on an inorganic core
and results in a decrease in the surface tension and in
stabilization of the nanoparticles against aggregation.
Data on nonmetal nanoparticles stabilized by polymers
are practically lacking. Of particular interest in this
respect are nanoparticles of amorphous selenium (nano-
), which exhibit not only unique photoelectric,
semiconductor, and X-ray sensitive properties, but also
extremely wide spectrum of biological activity.
It is known [1–6] that reduction of selenium ions in
polymer solutions involves two processes: formation
of selenium nanoparticles with a narrow unimodal
size distribution and adsorption of macromolecules on
them. These processes lead to the formation of spherical
nanostructures with high molecular weight, high density,
and diverse morphologies.
In this study we performed comparative analysis of
UV–visible absorption spectra of selenium-containing
nanocomposites stabilized by various types of polymeric
matrices with varied selenium : polymer weight ratio ν.
All the nanocomposites were prepared by a similar
procedure: The reaction was performed in aqueous me-
dium under the conditions (pH 3.1–3.3) when selenious
practically does not dissociate (pK 3.3) ,
at Т = 293 K and atmospheric pressure.
The reduction of H
with ascorbic acid C
in aqueous medium according to the equation
→ Se + 3H
O + 2C
leads to the formation of a sol of zero-valent selenium Se
(in the form of a red-orange solution) and dehydroascor-
bic acid. The sol is unstable in solution and precipitates in
24 h, and in 7–10 days selenium from the amorhous red
form transforms into another modiﬁ cation, gray metal-
lic selenium. The formation of zero-valent selenium by
this reaction is in agreement with the results of previous
As polymeric stabilizers (PSs) of selenium nanopar-
ticles we chose various types of polymeric matrices:
nonionic polymers (polyvinylpyrrolidone, PVP; oxy-
ethyl cellulose, OEC), a cationic polyelectrolyte (poly-
methyl sulfate, PDMAEM), and anionic polyelectrolytes
PAMS; polymethacrylic acid, PMAA). The structural
formulas and molecular weights of the polymeric stabi-
lizers are given in the table. The PS concentration was
0.1 wt % in all the cases.
To study the kinetics of the formation of nanocom-
posites, we chose a series of ν (ν = c
is the ratio of
the gravimetric concentrations of selenium and polymer):
ν 0.025, 0.05, 0.1, 0.15, and 0.2.