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Core–shell magnetosensitive nanocomposites (NC) based on single-domain magnetite (Fe3O4, core), with a shell consisting of hydroxyapatite (HA) and cytotoxic drug doxorubicin (DOX) layers have been synthesized. The processes of DOX adsorption on Fe3O4/HA surface from physiologic solution have been studied. DOX release into saline was found to decrease with growing of its quantity on NC surface. It has been determined that cytotoxic influence and antiproliferative activity of Fe3O4/HA/DOX NC with respect to Saccharomyces cerevisiaecells are characteristic for interaction of these cells with a free form of doxorubicin. Magnetic liquids containing Fe3O4/HA/DOX NC stabilized by sodium oleate and polyethylene glycol were prepared and investigated. It is shown that using the ensemble of Fe3O4carriers as a superparamagnetic probe, the Langevin’s paramagnetism theory, and the values of density of nanocomposite constituents, one can evaluate the size parameters of their shell, which has been corroborated by independent measurements of specific surface area of nanostructures and kinetic stability of the corresponding magnetic liquids. The obtained results may be useful for development and optimization of novel forms of magnetocarried medical remedies of targeted delivery and adsorbents based on nanocomposites of superparamagnetic core–shell type with multilevel nanoarchitecture, as well as for determination and control of the size parameters of its components.

Magnetosensitive nanocomposites on the basis of monodomain magnetite Fe3O4/meso-2,3-dimercaptosuccinic acid, Fe3O4/γ-aminopropyltriethoxysilane, Fe3O4/polyacrylamide, Fe3O4/hydroxyapatite were synthesized. Size distribution of magnetite nanoparticles in ensemble and their magnetic properties were studied. It has been shown that the magnetization curve of the liquid containing monodomain magnetite has a form that is characteristic for superparamagnetics, and its calculations in the framework of Langeven’s paramagnetism theory match satisfactorily to the experimental results. The highest adsorption parameters were observed for magnetosensitive nanocomposites Fe3O4/polyacrylamide and Fe3O4/γ-aminopropyltriethoxysilane. Prospects of the studied nanostructures for medicobiological and technical applications as adsorbents of cis-dichlorodiammineplatinum were shown.

On the basis of a similarity with electronic states in alkali-metal atoms, the existence of a new artificial atom (superatom) has been predicted theoretically. This superatom may be considered as a new alkali-metal atom.

Polymer composite materials based on CuS/CdS, Cu2S/CdS and Ag2S/CdS were obtained by substitution of Cd with Ag, Cu (II) and Cu (I) ions in the CdS rod-like nanocrystalline and investigated their electrophysical properties. It was found that the electrical conductivity of CuS/CdS heterostructure is in five orders higher compared to the CdS. It was shown that the values of the complex permittivity at identical content of CuS and Cu2S nanoparticles are more than 40 % higher for the 0.3 Cu2S/CdS-PVDF system in comparison with the 0.3 CuS/CdS-PVDF.

The influence of a homogeneous magnetic field on the electron states localized over the surface of an ellipsoidal dielectric particle by the electrostatic image forces is studied theoretically. The effects of the resonant interaction of light with such local electron states in presence and in absence of a homogeneous magnetic field are investigated.