2. Electrochemical simulation and regulation of redox-processes, which run in biosystems, with participation of oxygen and active intermediates of its reduction., determination of the effectiveness of antioxidants, electrochemical study and modeling of supramolecular interactions of bio-molecules.
A starting point in the
our Department is a creation in 1979 of the laboratory of
organic compounds in the Sector of Petrochemistry of the Institute of
Physical-Organic Chemistry and Coal Chemistry of NAS of Ukraine. Since
Department has been working as a part of the Bioorganic Chemistry and Petrochemistry of
Ukraine. Since April 2011 it has been renamed to the Department of
Functional Materials. From the very beginning and up to the summer of
2008 was headed
Dr. Galina S. Shapoval
. From the summer of 2008 and up to now
of the department is Prof.
Dr. Alexander A. Pud
Using our experience in
studies: of electrochemical properties and electrochemical
organic compounds on metal and carbon-containing (carbon fibers,
glass-carbon) electrodes, of electrochemical degradation and stability
dielectric and conducting polymers, cathodic delamination of polymer
and corrosive protection of metals, we have currently been concentrating
efforts 1. The development and study of properties
and search of applications of multifunctional hybrid (nano)composites
of electrically conducting polymers (e.g. polyaniline, polythiophene and
their derivatives) with both the polymers of other nature (including
common polymers) and inorganic nanostructured materials (semiconductor,
dielectric, magnetic nanoparticles etc.).
The chemical or
electrochemical polymerizations of the corresponding monomers in the
presence of other components of composite material are our main
approaches to form such materials. For example, as a reaction and,
simultaneously, template medium we utilize either dispersions of such
components or films impregnated with a monomer or its solution.
direction is based on studies of fundamental physical-chemical and
electrochemical aspects of the polymerization of initial monomers
(kinetics, a development of different stages of this process) and also
on studies of properties both of the electrically conducting polymers
and their composites as a whole. A significant attention is paid here to
preparation, synthesis and study of other components of such
Due to an effective combination of the properties
of all components, such materials are, as a rule, multifunctional i.e.
they can be used for different applications. For example, our
polyaniline-containing polymeric composites with the commercial polymers
(polyethylene terephthalate, polyvinylidene fluoride, polyamides,
polycarbonate etc.) are at least tri-functional and can be used as
antistatic and sensory materials and, in some cases, as p-type
semiconductors in photovoltaic heterostructures. Their effectiveness in
corrosion is also expected.
In the case of hybrid
composites of the conducting polymers with inorganic semiconductor or
magnetic nanoparticles or carbon fibers nanoparticles, which are formed
as guest-host (core-shell) heterostructures, we hope for applications in
sensor and biosensor studies, in photovoltaic and optoelectronics
devices, in supercapacitors, for preparation of luminescent nanoparticle
labels for biomedical studies etc.
In the framework of this direction, methodological approaches are proposed to simulate in vitro elementary stages of the starting reactions of oxygen stress of the living organism.
The pulse voltammetry based method has been developed, which allows to register the reactive oxygen species (ROS) and their reactions with biologically active substances (BAS) being both known and potential antioxidants (AO). This allows quick and easy determining the antioxidant activity of BAS as a whole, their antiradical and antioxidative abilities by their interaction with the electrochemically generated hydroxyl radicals and hydrogen peroxide respectively. On the basis of the approaches both the thin mechanism of action and effectiveness of natural and synthetic AO is investigated on the example of carboxylic acids, amino acids, number of flavonoids, vitamins, quinoline derivatives of cysteine and acetylcysteine, synthetic medications and extracts from the medicinal plants. The method makes it possible to determine optimum concentrations, to compose series of AO effectiveness depending on their structure and to predict effectiveness of new synthesized BAS as AO. The method makes it possible to reveal the most effective medications, which are capable to decrease a toxic action of radical ROS on the organism. Moreover, it allows establishing a synergetic effect of simultaneous action of several medications that opens the prospects for screening substances - synergists. The method also makes it possible to get some ideas about the influence of different solvents, ultraviolet and the small doses of radiation on the starting reactions of the oxygen stress of the organism.
The new developed approaches to the electrochemical studies of an antioxidant activity of the components of the blood allow to reveal the special features of the influence of leukocytes, lymphocytes, erythrocytes and plasma on ROS, and to fix also the difference in the antiradical activity of the healthy and transformed lymphocytes. Furthermore, the electrocatalytic model of the reactions, which occur in the organism under the effect of the metal ions of variable valence, is created. The use of this model makes it possible to forecast promising BAS as the preventive antioxidants. The used combination of voltammetric measurements with the study of BAS adsorption at the cathode under the potentials of the ROS formation offers some possibilities for a simulation of starting reactions of the oxygen stress, which take place on the surface of the negatively charged cellular membranes, as well as for a modeling of the self-assembled structure formation and for determination of values of supramolecular interactions of the bio-molecules functional groups.