XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
293
T6: P–1
Spectrophotometric determination of peroxides using citrate-stabilized
silver nanoparticles
Ekaterina Terenteva
1
, Aleksandra Kolomnikova
1
, Vladimir Apyari
1
, Alexey
Garshev
1,2
, Pavel Volkov
3
, Stanislava Dmitrienko
1
, and Yury Zolotov
1
1
Department of Chemistry, Lomonosov Moscow State University, 119991 Leninskie gory, 1/3,
Moscow, Russia, e-mail: apyari@mail.ru
2
Department of Materials Science, Lomonosov Moscow State University, 119991 Leninskie gory, 1/3,
Moscow, Russia
3
National
Research
Center
“Kurchatov Institute”
–
IREA,
107076
Bogorodsky
Val,
3,
Moscow,
Russia
Silver nanoparticles (AgNPs) attract special attention of researchers owing to their unique
properties underlying their wide usage in various fields of chemistry. The optical properties of
silver nanoparticles stem from the effect of surface plasmon resonance (SPR), being a basis of
their application in spectrophotometry. High sensitivity of AgNPs in combination with ease of
their production makes them a promising alternative to traditional spectrophotometric reagents.
Therefore, it is actual to search for new ways of the analytical application of AgNPs as a reagent
and expand the scope of their use in the chemical analysis.
In the present work, a possibility of using AgNPs stabilized with sodium citrate as a
spectrophotometric reagent for determination of peroxides is studied.
Silver nanoparticles stabilized with sodium citrate were prepared by the borohydride
method. They were characterized by transmission electron microscopy and electron diffraction.
It has been found that these AgNPs are easily oxidized in the presence of various
hydroperoxides, such as hydrogen peroxide, peracetic acid, m-chloroperbenzoic acid and t-
butylhydroperoxide. Disubstituted peroxides t-butylperbenzoate and di-t-butylperoxide affect
AgNPs in a lower extend. The oxidation of AgNPs is accompanied by a decrease in the SPR
band at 385 nm and discoloration of the solution. Dependence of the oxidizing effect on
structural peculiarities of a peroxide has been shown. The effects of various factors such as the
interaction time, pH, the concentration of a peroxide and AgNPs on their oxidation were studied.
The interaction takes 2–10 min and proceeds at pH 5–12 for the peracids; and 20–25 min, pH 7–
9 for the other hydroperoxides.
The AgNPs oxidation degree, which was characterized by a change in the absorbance at the
maximum of the SPR band (λ = 385 nm), increases with increasing peroxide concentration. It
can be used for spectrophotometric determination of the peroxides. Limits of detection decrease
in the following sequence: t-butylhydroperoxide > m-chloroperbenzoic acid > peracetic acid >
hydrogen peroxide and come to 1.3, 0.43, 0.1, and 0.066 μg mL-1. Using the proposed method,
the spectrophotometric determination of hydrogen peroxide in an antiseptic agent and in a hair
oxygenator was carried out. The results obtained were in good agreement with the data declared
by a manufacturer as well as with the results obtained by an independent method. The relative
standard deviations were not higher than 9 %. Advantages of the developed method are
simplicity, quickness, availability of the analytical equipment and ease of implementation as a
semi-quantitative test-measurement.
Keywords: silver nanoparticles; spectrophotometry; peroxides determination; surface plasmon resonance
Acknowledgment
This work was financially supported by the Russian Foundation for Basic Research (grant N 15-33-70002
mol_a_mos). The authors acknowledge instrumental support from M.V. Lomonosov Moscow State
University Program of Development.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
294
T6: P–2
New applications of silver triangular nanoplates and their polyurethane
foam nanocomposite for spectrophotometric and solid-phase
spectrometric determination of oxidizing agents in aqueous solution
Aleksei Furletov
1
, Vladimir Apyari
1
, Alexey Garshev
1,2
, Pavel Volkov
3
,
Stanislava Dmitrienko
1
, and Yury Zolotov
1
1
Department of Chemistry, Lomonosov Moscow State University, 119991 Leninskie gory, 1/3,
Moscow, Russia, e-mail: aleksei_furletov@mail.ru
2
Department of Materials Science, Lomonosov Moscow State University, 119991 Leninskie gory, 1/3,
Moscow, Russia
3
National
Research
Center
“Kurchatov Institute”
–
IREA,
107076
Bogorodsky
Val,
3,
Moscow,
Russia
Recently, silver nanoparticles have been widely used in various fields of analytical chemistry
due to their unique optical properties conditioned by the surface plasmon resonance (SPR),
which causes an intense absorption in the visible spectral region. These extra optical properties
are especially interesting for non-spherical silver nanoparticles, for example, triangular
nanoplates (AgTNPs), as they depend on the particle’s shape, size and state of the surface. This
fact could play a significant role in the development of new methods for determination of
different compounds. Immobilization of nanoparticles in solid matrices could improve stability
of these nanoobjects and provide synthesis of nanocomposite materials with SPR properties.
The objective of this study was to investigate the possibility of using AgTNPs and
nanocomposite material based on AgTNPs immobilized on polyurethane foam for determination
of oxidizing agents by spectrophotometry and diffuse reflectance spectroscopy.
Synthesis of AgTNPs was carried out by the borohydride approach. They were characterized
by transmission electron microscopy, electron diffraction and spectrophotometry. The average
length of AgTNP edge is 52 nm and the average thickness is 4 nm. AgTNPs have intense
absorption in the range of 600–800 nm and dark blue color. It was found that AgTNPs can be
easily oxidized by the interaction with oxidizing agents such as mercury(II) ions, hydrogen
peroxide, tert-butyl hydroperoxide and peracetic acid. The oxidation is accompanied by a
decrease of intensity of the SPR band at λ = 625 nm and its hypsochromic shift, which are
presumably caused by changes in morphology of the surface silver layer. Based on this fact, a
method for determination of the above-mentioned oxidizing agents in aqueous solutions has
been developed. The limits of detection are decreased as follows: tert-butyl hydroperoxide >
hydrogen peroxide > peracetic acid > mercury(II) ions, and are equal to 15, 1.6, 0.2 and 0.1 μM
respectively. Effects of the AgTNPs concentration, interaction time, pH and extraneous ions
were studied. It was found that the determination of oxidizing agents does not interfere with
1000-fold excess of common inorganic ions. The proposed approach was successfully used for
the analysis of real objects. Accuracy of the determination was confirmed by comparison with
independent methods. A new nanocomposite material based on polyurethane foam modified
with AgTNPs has been synthesized and its interaction with oxidizing agents has been studied.
The results showed that this nanocomposite can be used for determination of oxidizing agents by
the diffuse reflectance spectroscopy. This readily prepared solid-phase reagent is stable and
easy-to-use. Simplicity, low detection limits, availability of equipment and the possibility of
creating test-methods are the main advantages of the proposed approach.
Keywords: determination; diffuse reflectance spectroscopy; mercury(II); nanocomposite material;
oxidizing agents; peroxides; polyurethane foam; silver triangular nanoplates; spectrophotometry;
surface plasmon resonance
Acknowledgment
This work was financially supported by the Russian Science Foundation (grant N 14-23-00012). The authors
acknowledge instrumental support from M.V. Lomonosov Moscow State University Program of Development.
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