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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 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]

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]

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.)

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]