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Silicon (Si) nanoparticles (NPs) with small (10 À3 -10 À1 at%) content of iron oxide (Fe 2 O 3 ) are prepared by plasma-assisted ablative synthesis. Powders of the prepared Si-iron oxide (SIO) NPs are investigated by means of the transmission electron microscopy, Raman spectroscopy, electron paramagnetic resonance, and magnetic susceptibility measurements. Aqueous suspensions of the NPs are studied by using dynamic light scattering and nuclear magnetic resonance technique. The longitudinal and transverse relaxation times of protons in aqueous suspensions of the NPs are found to be dependent on the iron content. The stronger decrease of the proton relaxation is detected for the samples with higher iron content. Magnetic resonance imaging (MRI) experiments show that SIO NPs have properties of the MRI contrast agent and it is confirmed by in vivo experiments with cancer tumor. Aqueous suspensions of SIO NPs are explored as sensitizers of electromagnetic radio frequency hyperthermia and the highest heating rate is observed for the NPs with smaller hydrodynamic size (%50 nm). The obtained results indicate possible ways for applications of SIO NPs in the MRI diagnostics and mild therapy of cancer.

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The method of Raman scattering spectroscopy was used to study various silicon nanostructures (nanowires, mesoporous nanoparticles, crystalline and laser-ablated nanoparticles) dispersed in aqueous medium. The obtained results indicate different dissolution rate for silicon nanoparticles of different sizes and morphology in water that can be used for their potential biomedical applications.

The temperature of silicon nanoparticles under laser photo-induced heating is determined from the ratio of the intensities of the Stokes and anti-Stokes components of the Raman scattering. The obtained results of the dependence of nanoparticles temperature on the laser radiation intensity and the temperature dependence of the Raman line position maybe used to determine the optimal regimes of photo-hyperthermia enhanced by silicon nanoparticles for cancer therapy.

Structural-dynamic models of aspirin are proposed on the basis of non-empirical quantum calculations of geometrical and electronic structure. In this work, the parameters of the adiabatic potential are determined, and the interpretation of the vibrational states of the compound under study is proposed. Structural-dynamic models of its isomers are constructed, the signs of their spectral identification are revealed. The conformational structure of the molecules of the substance under study was analyzed. The choice of the method and the basis for calculating the fundamental vibration frequencies and band intensities in the IR and Raman spectra are substantiated. A method for estimating anharmonic vibrations using cubic and flat force constants is described. The article presents the results of a numerical experiment; the geometrical parameters of the molecules, such as the lengths of the valence bonds and the magnitudes of the angles between them, are determined. The frequencies of the vibrational states and the magnitudes of their integrated intensities are obtained. The interpretation of isomer vibrations is given and compared with the available experimental data. General regularities in the behavior of spectral bands of different isomers are shown. Frequencies that can be used to identify the isomer from the vibrational spectra of molecules are proposed. The calculation was carried out by the DFT/B3LYP density functional quantum method. It is shown that this method can be used to model the geometrical parameters of molecules and the electronic structure of various substituted benzoic acid. It allows to construct structural-dynamic models of the specified class of compounds on the basis of numerical calculations.

We studied a biocompatibility and a bioprotector property of nanodiamond composites on reduction of the toxic action to cadmium salt. The experimental animal intragastric received with the help of a probe activated carbon and nanodiamond composite. We researched the rate of spontaneous and ascorbate-dependent lipids peroxidation and the reference level of malonic dialdehyde in liver, thyroid and adrenal glands tissues. So this concentration of the nanopore material at intragastric entering did not led to difference of researched parameters of the lipid peroxidation. The solution of cadmium salt developed typical for it toxic action which expressed in increase intensity of the processes of POL in liver and thyroid gland tissues. The nanopore material developed the characteristic which screened the toxic action of cadmium chloride and it was more denominated on some parameters in comparison with the effect of the intragastric entering of the activated carbon.

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