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With the development of nanotechnology, new scientific directions have been initiated and a significant amount of researches has been carried out, dedicated to the creation and search for promising applications in medicine, in particular, oncology, of nanocomposites based on bioinert, biocompatible and bioactive nanoparticle materials and modern chemotherapeutic drugs with different mechanisms of action. These works contain data indicating the advantages to introduce nanocomposite drugs into clinical practice, compared to the traditional use of chemotherapeutic drugs. The research results confirm the priority of works in the field of creation of new nanocomposite chemotherapeutic drugs for use in antitumor therapy and overcoming of drug resistance of malignant cells and neoplasms. The purpose of the review is to generalize and analyze the authors’ experimental works performed at Chuiko Institute of Surface Chemistry of National Academy of Sciences of Ukraine, concerning the specifics of the effect of chemotherapeutic drugs with different mechanisms of action and related nanocomposites, on cellular systems and tumors. Such data are relevant to determine promising directions and ways of creation of new effective nanocomposite drugs for use, in particular, in antitumor chemotherapy. At Chuiko Institute of Surface Chemistry of National Academy of Sciences of Ukraine, using the chemical engineering method, magnetically sensitive core-shell nanocomposites were synthesized with a multi-level hierarchical nanoarchitecture capable of performing a complex of diagnostic and therapeutic functions with various mechanisms of action, characteristic of medico-biological nanorobots. Their use makes it possible to implement the principle of targeted delivery of antitumor drugs, to carry out real-time local therapy by various methods and MRI diagnosis of the disease, to realize the synergy of treatment with antitumor drugs of different mechanisms of action, to reduce the toxic side effects of oncological drugs on the body. The combination of the above features of nanocomposites, as well as their role in overcoming the drug resistance of cells of malignant neoplasms to cisplatin, testify to the perspective of creation and research of nanocomposite drugs in solving the problem of increase in the efficiency of chemotherapy. [ABSTRACT FROM AUTHOR]

Nanocomposites containing components with semiconductor, ferroelectric, and ferromagnetic properties have attracted considerable attention of specialists due to the range of possible applications, including catalysis and electrocatalysis, electrode materials for solar and fuel cells, capacitors, electrical and biosensors, anti-corrosion coatings and much more. In recent years, both fundamental and applied interest in this direction of research is due to the possibility of creating a new type of controlled microwave devices and tools. The aim of the work is to develop methods for the synthesis of nanostructured NiCo composites based on BaTiO3 and TiO2, as well as to find the differences and regularities of their physicochemical properties. Two series of samples with different content of NiCo nanoparticles based on titanium oxide (TiO2) and barium titanate (BaTiO3) were obtained. NiCo particles were obtained by the method of chemical precipitation of nickel and cobalt carbonates in equal parts from a hydrazine hydrate solution at the temperature of 350 K. The results of X-ray phase analysis indicate the chemical purity of the obtained samples. The values of ε′, ε″ at a frequency of 9 GHz for the NiCo/BaTiO3 system are twice as high compared to NiCo/TiO2 for the corresponding values of the NiCo content, which is due to the higher values of ε′, ε″ of the initial barium titanate. Electrical conductivity of NiCo/BaTiO3 system changes by six orders of magnitude, which indicates the formation of a continuous percolation cluster of metal particles on the surface of dielectric BaTiO3 particles. The composites are heat-resistant up to 630K, as shown by the method of thermogravimetry and pronounced magnetic properties. The program for calculating frequency dependences of reflection and absorption coefficients in a complex form has been developed. EMF absorption for composites from the radiation frequency and the position of the minima of these characteristics, which agree satisfactorily with the experiment. The obtained composites can be promising components for obtaining composite systems and paints for protection against electromagnetic radiation. [ABSTRACT FROM AUTHOR]

The processes of carbonization of sucrose-containing coatings on the surface of single-domain magnetite and magnetosensitive nanocomposite (MNC) Fe3O4/Al2O3 are studied. The MNC with a carbon surface is synthesized by the method of low-temperature pyrolysis of carbohydrates. As revealed, the used heat-treatment mode does not lead to deterioration of the magnetic characteristics of magnetite under the condition of preliminary creation of a protective layer of alumina on its surface. Differential thermal analysis (DTA) in combination with differential thermogravimetric analysis (DTGA) and programmed temperature-desorption mass spectrometry show that the carbonization of sucrose under these conditions is complete. The shape and dimensions of the Fe3O4, Fe3O4/Al2O3 and Fe3O4/Al2O3/С MNCs are investigated by the TEM method. As established, the values of the specific saturation magnetization of MNCs are consistent with the corresponding changes in the mass fraction of magnetite in the Fe3O4/Al2O3 and Fe3O4/Al2O3/С structures. The results of TEM studies and magnetic measurements indicate the formation of the Fe3O4/Al2O3 and Fe3O4/Al2O3/С MNCs by the core–shell type. Methylene blue is used to study the adsorption activity of the Fe3O4/Al2O3/С MNC surface. The results of the work can be used in the development of new magnetically controlled adsorption materials for medical–biological purposes. [ABSTRACT FROM AUTHOR]

The creation of new nanomaterials for absorbtion of electromagnetic radiation microwave range is an important direction in consequence of electromagnetic pollution of the environment. The aim of the paper was to develop and synthesize the polymer-filled systems based on the polychlorotrifluoroethylene and tin dioxide modified by nickel ferrite in order to study their electrophysical properties as potential materials absorbing electromagnetic radiation. NiFe2O4/SnO2 nanocomposites with a volume content of nickel ferrite on the surface of tin dioxide from 0.62 to 0.8 were synthesized by co-precipitation. Size of SnO2 and NiFe2O4 nanoparticles was determined by a transmission electron microscope and its about 30–50 nm and 15–30 nm, respectively. For the NiFe2O4/SnO2 nanocomposites the values of complex permittivity and complex permeability in the microwave range, values of conductivity at low frequencies were investigated. Maximum values of complex permittivity and complex permeability were found for NiFe2O4/SnO2 nanocomposites at the volume content of nickel ferrite 0.62. An increase was observed in the complex permittivity for the NiFe2O4/SnO2–polychlorotrifluoroethylene system, 2–3 times greater than the values related to the NiFe2O4/SnO2 nanocomposites. The electrical conductivity at low frequencies (100 Hz) of polymer composites increases by an order of magnitude with a decrease of the concentration of nickel ferrite on the surface of tin dioxide. It was found that the calculated absorption coefficient of an electromagnetic wave in the frequency range 1–41 GHz for NiFe2O4/SnO2 nanocomposites is about 2 times greater than that for nickel ferrite. It is shown that the creation of nanocomposites based on a conductive component modified by a magnetic component is more efficient for the processes of absorption of electromagnetic waves in the microwave range at optimal ratios of the values of the permittivity and permeability than pure ferrite. [ABSTRACT FROM AUTHOR]

The aim of the work is the synthesis and study of the bioactivity of sol-gel glass (BG 60S) with molar composition 60 % SiO2, 36 % CaO, 4 % P2O5 and samples doped with La and Y in vitro; studying their structural properties and changes upon contact with a model physiological environment (Kokubo’s SBF), as well as justifying the possibility of their use for tissue regeneration and tissue engineering. According to the results of research, the interaction of synthesized samples with SBF leads to a change in the phase composition and the ratio of amorphous and crystalline components. It is necessary to note long and intensive processes involving CO3 2– ions for unalloyed and alloyed samples. The appearance of calcium carbonate in the form of vaterite with a simultaneous increase in the calcite content is one of the signs of high bioactivity of the synthesized samples. According to the results of XRD, EDX and FTIR studies after 28 days of soaking in SBF, the predominant surface elements are Ca and P in the composition of hydroxyapatite, and the elemental composition indicates active ion exchange processes according to the theory of bioactive glass dissolution in physiological fluids. The change in the ratio of crystalline phases with the inclusion of mainly one crystalline phase of hydroxopatite within 28 days leads to a better structuredness of the surface of the synthesized samples and indicates that they have osteoconductive properties, can connect with bone tissue and have the appropriate biodegradation ability. The results of the study indicate the promising nature of synthesized materials for tissue regeneration and tissue engineering. [ABSTRACT FROM AUTHOR]

The purpose of the work is the synthesis of samples of X-ray luminescent nanodispersed lanthanum phosphate activated with terbium (LaPO4:Tb3+), the study of their structural properties and luminescence spectra when excited by ultraviolet and X-ray radiation, as well as determination of the possibility of their use in nanocomposites with bioactive glass and colloidal nanosystems. Samples of nanocrystalline lanthanum phosphate were synthesized composed of LaPO4∙0.5H2O, of hexagonal syngonium, activated with terbium, their structural properties, luminescence spectra were studied upon excitation by UV and X-ray radiation, a possibility was shown to use them in nanocomposites with bioactive sol-gel glass and aqueous colloidal systems. Composites of 60S bioglass with nanodispersed crystalline LaPO4:Tb3+ in the dry state and in distilled water medium demonstrated the presence of luminescence when excited by UV and X-ray radiation. The given data indicate the perspective of nanodispersed phosphors based on lanthanum phosphate, their composites with bioactive sol-gel glass in colloidal systems, for use in optopharmacology and photodynamic therapy of diseases localized in bone tissues. In addition, the results of research can be useful for technical applications, in particular, in the creation of luminescent detectors of high-energy electromagnetic radiation, development of photo- and optoelectronic devices, etc. [ABSTRACT FROM AUTHOR]

Nanosize nickel ferrite was synthesized by the sol-gel autocombustion method. The surface of nickel ferrite was modified by copper sulphide with the volume fractions from 0.2 to 0.42. For the CuS/NiFe2O4 composites the values of complex permittivity and permeability in the microwave range, values of conductivity at low frequencies and magnetic characteristics were investigated. Polymer composites CuS/NiFe2O4-polychlorotrifluoroethylene (PCTFE) were obtained by hot pressing technique. With an increase in the content of copper sulphide of polymer composites, an increase in the values of the complex dielectric constant in the microwave range of 2-3 times was observed. The values of electrical conductivity for the 0.2CuS/NiFe2O4-PCTFE system are 4-5 orders of magnitude lower than for the 0.42CuS/NiFe2O4-PCTFE system with an increase in the concentration of copper sulphide in polymer composites. The change in the ratio of the conducting and magnetic components in the studied system makes it possible composites with adjustable permittivity and permeability in the microwave range. [ABSTRACT FROM AUTHOR]

The aim of the work was to study the peculiarities of interaction of the surface of bacterial lectin of Bacillus subtilis IMB B-7724 inthe native state and under different model conditions with water molecules by ¹ H NMR; to create a composite system based on the studied lectin, in which the protein molecule is minimally affected by the surface of the carrier, because protein molecules are capable to bind a significant amount of water localized in the spaces between the polymer chains. A method of “dry” immobilization of bacterial lectin on the surface of hydrophobic silica has been developed.Hydration of native lectin and lectin fixed on the surface of hydrophobic silica AM-1-175 was studied by low-temperature ¹ H NMR spectroscopy. It has been shown that the immobilization of lectin on the surface of AM1 is accompanied by an increase in the interfacial energy gS from 4.1 to 5.2 J/g. This is due to an increase in the concentration of strongly bound water. Analysis of changes in the distributions of radii R of clusters of adsorbed water allows us to state that in water adsorbed by native lectin, there are two main maxima at R = 1 and 3 nm. In the immobilized state, the maximum at R = 1 nm is present in both types of water (of different order), but the second maximum is observed only for more ordered associates.Chloroform medium slightly reduces the binding energy of water to native lectin molecules (from 4.3 to 4.1 J/g), but in the case of immobilized lectin in CDCl3 medium, the value of ΣgS increases from 5.2 to 7.4 J/g. That is, the weakly polar medium promotes to increase in the interaction of water with interfaces, which is manifested in a relative increase in the number of water clusters of smaller size (Fig. 4). It should be noted that weakly associated forms of water (signal 3) are also represented by several types of clusters that have a radius in the range R = 1–10 nm, and their size distribution changes significantly during immobilization of lectin on the surface of AM1. Probably, weakly associated types of water are formed both in cavities, between polymer chains of protein molecules, and on the surface of AM1, free of protein. [ABSTRACT FROM AUTHOR]

One of the most widely used antitumor chemotherapeutic drugs is “Cisplatin” (active substance - cis - diaminodichloroplatinum), the side effects of which are the cumulative ototoxic, nephrotoxic and neurotoxic effects. The use of drug carrier systems for targeted delivery and adsorbents for extraction, in particular magnetite-carbon nanocomposites, will minimize unwanted toxic effects without reducing the therapeutic effect of cisplatin. For this purpose, a nanocomposite (NCs) of Fe3O4/Al2O3/С with a carbon surface was synthesized, where a layer of alumina protects magnetite during the pyrolysis of carbohydrates. The synthesized samples were characterized by TEM, XRD, mass spectrometry methods, magnetic properties and specific surface area were studied. It has been found that the used heat treatment mode (T = 500 °С, argon medium) is sufficient for complete carbonization of sucrose and preserves the phase of magnetite which does not lead to deterioration of magnetic characteristics. The results of TEM studies and magnetic measurements indicate the formation of the Fe3O4/Al2O3/С nanocomposite of the core-shell type. The adsorption of Cisplatin on the surface of NCs Fe3O4/Al2O3/С was performed and the adsorption process dependent on the contact time, pH of the solution and cisplatin concentration was studied. The experimental results of kinetic studies were analyzed for compliance with the theoretical models of Boyd and Morris-Weber, models of pseudo-first and pseudo-second orders. Langmuir and Freundlich isotherm models were used to model adsorption processes. The limiting factor of adsorption is the external diffusion mass transfer processes, which correlates with the calculated parameters of the pseudo-first-order model (r² = 0.985). The correlation of theoretical and practically obtained values of adsorption capacity indicates the possibility of using the Freundlich model to describe the adsorption of Cisplatin on the surface of Fe3O4/Al2O3/C. [ABSTRACT FROM AUTHOR]

The aim of the work is the synthesis of nanostructures based on lanthanum fluoride, promising for use in photodynamic therapy of tumors in organs of cranial cavity and bone tissues; a study of their structural properties and luminescence spectra. Synthesis of LaF3:Tb3+ was carried out by coprecipitation of components from aqueous and alcoholic (methanol) solution. As precursors were used: La(NO3)3×6H2O, TbCl3, NH4F. All reagents have qualification “chemically pure”. Distilled water and methanol were used as solvent. The synthesis of nanosized magnetite in the single-domain state was performed by the Elmore method. Synthesized nanodisperse samples are characterized by XRD analysis, DTGA, TEM. The magnetic properties and spectra of UV luminescence were also studied. It has been found that the XRD-patterns of LaF3:Tb3+ samples synthesized in water and methanol do not differ fundamentally. Under the experimental conditions, the most perfect crystals of hexagonal syngony were formed during crystallization in an autoclave. Their average size was ~ 15 nm. In TEM images, the length of the crystals exceeds the width by 3–4 times. Crystals are prone to aggregation and the formation of chain structures. The UV luminescence spectrum of the synthesized nanodisperse samples in aqueous medium at the concentration of 0.5 mg/ml and excited by ultraviolet radiation is characteristic of the structure of LaF3:Tb3+. Ensembles of particles Fe3O4/LaF3:Tb3+ NCs were synthesized. Transmission electron microscopy has shown that the shapes of particles of NCs and LaF3:Tb3+ nanocrystals are fundamentally different. Particles of Fe3O4/LaF3:Tb3+ NCs have a spherical shape, which is characteristic of structures of the core-shell type. X-ray diffraction patterns of NCs confirm this conclusion. The conditions for the synthesis of NCs did not significantly change the magnetic properties of their nuclei, single-domain Fe3O4 nanoparticles (NPs). The luminescence spectrum of Fe3O4/LaF3:Tb3+ NCs differs significantly from the spectrum of samples of nanodispersed LaF3:Tb3+ both in intensity and in the structure of the bands. These spectral differences may be due to differences in structure, features of the nanocrystalline structure, the content of the LaF3:Tb3+ scintillator and Tb3+ ions in samples of LaF3:Tb3+ nanocrystals and shells of Fe3O4/LaF3:Tb3+ nanocomposites. Composites of dispersed 60S bioglass with nanodispersed crystalline LaF3:Tb3+ in the dry state, and distilled water, showed the presence of luminescence upon excitation by UV radiation. The results of research show the prospects of the synthesized nanodispersed luminophors LaF3:Tb3+, for use as a source of luminescent radiation in optopharmacology and photodynamic therapy of tumors in organs of cranial cavity and bone tissues. Optimization of luminescent properties of the original nanodispersed luminophors, their compositions with bioactive glass, luminescent shells in the composition of magnetosensitive NCs, as well as the technology of manufacturing of these structures will significantly allow us to improve their performance characteristics. The results of the work indicate the prospects of the synthesized structures for further research under the conditions of excitation by high-permeability “soft” Xray radiation for use in optopharmacology and photodynamic therapy of tumors in organs of cranial cavity and bone tissues. Optimization of properties of the original nanodispersed luminophors, their compositions with bioactive glass and magnetosensitive carriers Fe3O4 will allow us to improve significantly their performance characteristics. [ABSTRACT FROM AUTHOR]

Сombination of properties of lectins and magnetically sensitive iron-containing nanocomposites (NC) for use in oncology is actual and promising from scientific and applied point of view. The aim of the research is to synthesize and to study new iron-containing NC and magnetic fluids containing bioactive bacterial lectin, promising for use as prototypes of new effective antitumor vector systems for targeted drug delivery and combined local therapy of cancer with minimized side effects on the body and improved compatibility with other remedies. To create vector systems, nanodisperse magnetite was synthesized by the Elmore reaction. The synthesis of aluminum-containing coating on the surface of Fe3O4 was carried out by double chemical modification with aluminum isopropylate. The obtained Fe3O4/Al2O3 NC was impregnated with sucrose solutions. Carbonization of the carbohydrate shell of NC was carried out in argon (500 °C). As a result, Fe3O4/Al2O3/C NC was obtained. The magnetic properties of nanostructures were measured using a laboratory vibration magnetometer of Foner type at room temperature. Adsorption immobilization of lectin was performed in 0.9 % NaCl solution in a dynamic mode at room temperature. Bacterial cytotoxic lectin of B. subtilis IMB B-7724 was used in the experiments. The amount of adsorbed substance (A) on the surface of nanocomposites was determined by measuring the concentration of lectin in the contact solutions before and after adsorption using a calibration graph. Measuring of the optical density and absorption spectra of lectin was performed on a spectrometer Lambda 35 UV/vis Perkin Elmer Instruments at λ = 280 nm. Standard techniques and equipment were used for biological research. The processes of adsorption immobilization of cytotoxic bacterial lectin of B. subtilis IMB B-7724 from physiologic saline on the surface of magnetite and carbon-containing Fe3O4/Al2O3/C NC were studied at room temperature. It has been found that the adsorption capacity of lectin on the surface of magnetite is 25.3 mg/g, and Fe3O4/Al2O3/C NC – 36.3 mg/g (at initial concentrations of lectin 0.06–0.4 mg/mL). The extraction extent of lectin R (%) was 12–38 % for magnetite and 46–67 % for Fe3O4/Al2O3/C NC. The dependence of the adsorption capacity on time was studied. A magnetic fluid (MF) based on single-domain Fe3O4, containing lectin was synthesized and investigated. Immobilization of lectin on MF particles was carried out in a dynamic mode at room temperature for 3 hours. The concentration of lectin in the composition of MF was 0.2 mg/mL. MF with immobilized lectin was further modified with PEG-2000. The synthesis of Fe3O4/ol.Na/lectin/PEG (ol.Na – sodium oleate) vector system was carried out in a dynamic mode for 3 hours. Modification of the surface of nanoparticles with polyethylene glycol was performed in order to increase the stability of the magnetic fluid, reducing the aggregation of particles. To determine the effect of experimental samples on the viability of MCF-7 cells in vitro, the following samples were prepared: Fe3O4/ol.Na/PEG (MF), CFe3O4 = 3 mg/mL; cytotoxic lectin of B. subtilis IMB B-7724 (CL), CCL = 0.2 mg/mL; nanobiocomposite (NBC). Nanobiocomposite based on MF and bacterial lectin was found to have a synergistic cytotoxic effect on MCF-7 human breast cancer cells, causing up to 40 % cell death. The IC50 values for the nanobiocomposite and lectin in relation to MCF-7 cells were 100 and 125 μg/mL, respectively. The results of research show that the combination of properties of lectins and magnetically sensitive ironcontaining NC for use in oncology is a promising direction in creating new effective antitumor vector systems for targeted drug delivery and combined local therapy of cancer. The use of natural components in vector systems is a way to minimize the side effects on the body and improve compatibility with other antitumor remedies. [ABSTRACT FROM AUTHOR]

Nanoscale magnetite (Fe3O4) and nanocomposite based on it (Fe3O4/SiO2) were synthesized. In solutions of different ionic strength (0.015 and 0.15 M NaCl) by pH-metry, the acid–base properties of the surface were studied: the pH value of the isoin state of the surface (рHIIP), the total concentration, and values of Ki and pK of surface hydroxyl groups active in the pH range 4–9 and are calculated dependencies of the particles of hydroxyl groups of the surface on the pH of the medium. It was found that neutral hydroxyl groups are predominant for the synthesized sample magnetically sensitive nanoparticles (MNPs), which make it possible to form centers of both acidic and base types. Thus, for Fe3O4 to pH = 6 active base centers (C=155.56⋅10−5 − 141.59⋅10−5 mol⋅g−1), the strength of which decreases with decreasing pH (pK = 2.65 ± 0.01–4.48 ± 0.01 (2.59 ± 0.003 − 4.70 ± 0.008 for 0.15 M NaCl solution). Acid centers in a very small amount (4.93⋅10−6 − 2.68⋅10−6 mol⋅g−1) are fixed in the pH range 7–9 and show weakly acidic properties (pK = 10.95 ± 0.21 − 11.31 ± 0.18 (11.34 ± 0.04 − 11.94 ± 0.17 for 0.15 M NaCl solution). For the Fe3O4/SiO2 surface, neutral centers are predominant, which are characterized by the detection of acidic properties, which makes it possible to form acid-type centers, the concentration of which is higher in 0.15 M NaCl solution (C = 237.58⋅10−5 mol⋅g−1), (C for 0.015 M NaCl solution = 150.54⋅10−5 mol⋅g−1), whose strength decreases with increasing pH (pK2=4.69 ± 0.03 − 8.6 ± 0.08 (4.91 ± 0.1 − 9.32 ± 0.09 for 0.15 M NaCl solution)). [ABSTRACT FROM AUTHOR]

Polymeric construction materials based on epoxy resin, carbon fillers, such as graphene nanoplates (GNP), carbon nanotubes (CNT) and fillers of inorganic nature – perlite, vermiculite, sand with improved electrophysical characteristics have been developed. The electrophysical propertieгs of composites obtained in various ways which differ according to the principle of injecting components have been investigated. GNP were obtained in two ways. Size distribution of GNP obtained by electrochemical method is 50 to 150 nm. The average particle size is up to 100 nm. It occurs that these particles tend to aggregate as it is shown by the method of dynamic light scattering. The GNP obtained by dispersing thermally expanded graphite in water in a rotary homogenizer have a particle size distribution of 400 to 800 nm if very small particles and large aggregates are absent. The second method of obtaining GNP is less energy consuming and requires fewer manufacturing cycles, so it is more cost-effective. Obtaining composites using aqueous suspensions of GNP is environmentally friendly. Due to the hydrophobic properties of its surface the electrical conductivity of the system which uses vermiculite is higher than one of that which uses perlite for composites with CNT and GNP. It has been found that the difference of electrophysical characteristics between two systems which contain the same amount of carbon filler is caused by the nature of the surface of dielectric components – sand. By changing the content of dielectric ingredients can expand the functionality of composites if use them for shielding from electromagnetic fields. [ABSTRACT FROM AUTHOR]

Barium ferrites modified with copper iodide were synthesized by the sol– gel-autocombustion method. The sizes of barium-ferrite crystallites for all samples were of 20–50 nm. The magnetic and electrophysical properties of CuI/ferrite-filled polychlorotrifluoroethylene (PCTFE) composites are investigated in the microwave range at ambient temperature. As shown, the introduction of CuI/ferrite composites into PCTFE leads to an increase of the values of the complex dielectric permittivity magnitude by 2–5 times in comparison with the system containing the unmodified component. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this work is to develop a simple, cheap and reproducible method for the synthesis of stable magnetic fluid nanocomposite chitosan/magnetite with particle size less than 100 nm and to study some of its physical and chemical properties. As a result, the method of synthesis of polyfunctional hybrid magnetic liquid nanocomposite chitosan/magnetite/sodium oleate with multilevel architecture was developed. With methods of small-angle neutron scattering, infrared Fourier spectroscopy, and transmission electron microscopy the structural characterization of the obtained magnetic nanofluids was performed. The formation of aggregates in magnetic fluids is established based on results from small-angle neutron scattering. The scattering signal from fractal particles was obtained simultaneously with the signal of small-angle neutron scattering for polydispersed spherical particles in the studied liquid systems. The mechanism of interaction of sodium oleate with chitosan in the system of chitosan/magnetite/sodium oleate is proposed. It has been shown that the binding between magnetite/sodium oleate and chitosan can be explained by the electrostatic interaction between a positively charged chitosan molecule and negatively charged coating of sodium oleate on the surface of magnetite. Strong electrostatic interaction also leads to the proton transfer from oleic acid to chitosan, thus creating a stable complex. The synthesized nanocomposite can be potentially used for targeted drug delivery and deposition of drugs in target cells and organs, for the diagnostics and therapy of diseases at the cellular level. [ABSTRACT FROM AUTHOR]

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The method for chitosan (CS) covalent immobilization onto NH2-functionalized magnetite nanoparticles surface is presented. Covalent binding of CS to the magnetite surface proceeds using a free -CH2OH group of CS and a NH2-group of magnetite with epichlorohydrin (ECH) as a cross-linker. The obtained nanocomposites were functionalized by diethylenetriaminepentaacetic acid (DTPA)-groups. Composites were characterized by elemental analysis, FTIR, XPS and ASAP methods. The total content of organic phase (CS-DTPA) in the hybrid material, appreciated by thermogravimetric analysis (TGA), was 3.7%. Considering the atomic ratio between oxygen in CS and oxygen in ECH residue, the chemical structure of the hybrid material is proposed. The adsorption of Gd-DTPA and Gd3+on the obtained nanocomposite was studied. The Freundlich isotherm fits all the experimental data better than the Langmuir adsorption. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The arrays of nanorods of zinc oxide on the template of anodized aluminum oxide have been fabricated by electrochemical decomposition of molecular oxygen in the presence of Zn2+. The template was prepared by anodizing Al foil and Al films deposited in vacuum in oxalic acid. The formation of nanorods was confirmed by scanning electron microscopy. The X-ray phase analysis and Auger electron spectroscopy data have confirmed that the structure and composition of the nanorods correspond with those of zinc oxide. [ABSTRACT FROM AUTHOR]

In order to synthesize the polymer composite system of the PCTFE-CuS/ZnS, the nanodispersed ZnS was synthesized by hydrothermal method afterwards heterostructures of CuS/ZnS were obtained using ion-substitution mechanism. The concentration dependence of the real and the imaginary components of the complex dielectric permeability and electrical conductivity of synthesized samples were investigated. Obtained composites have high values of the dielectric permeability at high frequencies and conductivity at low frequencies. At 50 % (molar) substitution of Zn ions by Cu the percolation threshold was determined at the volumetric content of CuS about 0.06. [ABSTRACT FROM AUTHOR]

A method has been developed of biomimetic hydroxyapatite (HA) biocompatible functional layer synthesis on the surface of the models of titanium articles of biomedical applications. Carboxyl-modified titanium surface acts as active nucleation site in biomineralization processes of HA synthesis which occurs in simulated body fluids (SBF) of different composition. A comparative study has been conducted on the influence of thermal conditions on the formation of HA in SBF of different chemical composition. The formation of hydroxyapatite coating on the surface of titanium has been confirmed by FTIR spectroscopy and XRD. [ABSTRACT FROM AUTHOR]

Nanocomposites containing components with semiconductor, ferroelectric, and ferromagnetic properties have attracted considerable attention of specialists due to the range of possible applications, including catalysis and electrocatalysis, electrode materials for solar and fuel cells, capacitors, electrical and biosensors, anti-corrosion coatings and much more. In recent years, both fundamental and applied interest in this direction of research is due to the possibility of creating a new type of controlled microwave devices and tools. The aim of the work is to develop methods for the synthesis of nanostructured NiCo composites based on BaTiO3 and TiO2, as well as to find the differences and regularities of their physicochemical properties. Two series of samples with different content of NiCo nanoparticles based on titanium oxide (TiO2) and barium titanate (BaTiO3) were obtained. NiCo particles were obtained by the method of chemical precipitation of nickel and cobalt carbonates in equal parts from a hydrazine hydrate solution at the temperature of 350 K. The results of X-ray phase analysis indicate the chemical purity of the obtained samples. The values of ε′, ε″ at a frequency of 9 GHz for the NiCo/BaTiO3 system are twice as high compared to NiCo/TiO2 for the corresponding values of the NiCo content, which is due to the higher values of ε′, ε″ of the initial barium titanate. Electrical conductivity of NiCo/BaTiO3 system changes by six orders of magnitude, which indicates the formation of a continuous percolation cluster of metal particles on the surface of dielectric BaTiO3 particles. The composites are heat-resistant up to 630K, as shown by the method of thermogravimetry and pronounced magnetic properties. The program for calculating frequency dependences of reflection and absorption coefficients in a complex form has been developed. EMF absorption for composites from the radiation frequency and the position of the minima of these characteristics, which agree satisfactorily with the experiment. The obtained composites can be promising components for obtaining composite systems and paints for protection against electromagnetic radiation. [ABSTRACT FROM AUTHOR]