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The effect of TiCl₄ hydrolysis temperature on the structural, textural and morphological properties of the resulting rutile and on the changes of these properties upon calcination was studied. The XRD, Raman spectroscopy, mercury porosimetry, BET, SEM and TEM studies have revealed that TiO₂ rutile has a hierarchical 3D-architecture. The obtained nanostructured rutile had a cauliflowerlike/ spherical morphology composed of fan-shaped nanofibers. Rutile samples were shown to have a heterogeneous pore structure including micro-, meso- and macropores with a BET surface area of 110-140 m₂/g. According to the mercury porosimetry, among mesopores and macropores the latter dominate in the samples. Elevation of the synthesis temperature from 50-70 to 80-90 °C decreased the fraction of macropores from 95 to 70%. The BET method showed that the samples synthesized at low temperatures (50-70 °C) contain 30-44% of micropores in the total amount of mesopores and micropores. The fraction of micropores decreases to 25-18% with a subsequent increase in the fraction of mesopores as the synthesis temperature is raised to 80-90 °C. As shown by a study of the samples upon calcination in the temperature range of 100-1000 °C, temperature is the key factor that produces changes in the crystallites size, nanofiber length and packing density, and 3D particle shape at different levels of the hierarchical system and determines features of the porous structure and morphological properties of nanostructured rutile. The assessment of photocatalytic activity in the oxidation of acetone vapor demonstrated that, regardless of the hydrolysis temperature, the synthesized samples of nanostructured rutile are able to oxidize acetone vapor to carbon dioxide and water. In the process, activity of the samples is comparable with that of commercial photocatalysts under UV light and is superior to the activity of commercial photocatalysts P25 (2-4 times) and TiO₂ KRONOS vlp 7000 (1.2-2 times) under visible light in dependence on the synthesis temperature.

To develop new catalysts based on carbon nanomaterials with supported metal oxide nanoparticles for oxidative transformations of sulfur compounds, a series of metal oxide nanoparticle-decorated carbon nanotubes (MOx/CNTs) were prepared by incipient wetness impregnation at a variation of the active metal type (M = Ce, Mo, Cu). The thermal decomposition of bulk and CNT supported metal precursors used in the preparation of MOx/CNTs was analyzed under inert atmosphere employing several thermoanalytical techniques (thermogravimetry, differential thermogravimetry and differential scanning calorimetry) coupled with mass spectrometry. The thermolysis parameters of the bulk and supported metal precursors were compared and the effect of CNT support on the decomposition pattern of compounds was elucidated. It was established that the decomposition of metal precursors supported on CNTs was started and completed at temperatures of 15‒25 and 25‒70 °C lower, respectively, compared with the bulk active metal precursor. The enhancement of CNT support stability against thermal degradation is observed in the following row of metal cations: Ce < Cu < Мо < pristine and metal anions of precursor: nitrate < chloride < sulfate. The optimal mode of thermal treatment of catalyst and appropriate active metal precursors were selected for advanced synthesis of nanosized MOx/CNT catalyst.

The role of acid treatment of Taunit carbon nanotubes in the formation of oxygen-containing functional groups on its surface as well as morphological and textural properties was studied. Acid treatment was carried out in an HNO3 solution or its mixture with H2SO4 under mild conditions (85 °C/1 h) with subsequent washing with distilled water or without washing. Properties of the initial and oxidized samples were investigated using elemental carbon, hydrogen, nitrogen, oxygen (CHNO) analysis, BET (Brunauer-Emmett-Teller) determination of surface area, X-ray diffraction, Raman and Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy, and hydrogen temperature-programmed reduction. Treatment with HNO3 and HNO3/H2SO4 mixture was shown to be efficient for the formation of various oxygen-containing groups on the Taunit surface; therewith, the water washing step also contributed to functionalization of the surface. Depending on the oxidant, acid treatment increased graphite and oxygen content in the samples by a factor of 3‒4.5. Treatment with HNO3 without water washing exerted a weak effect on the graphite structure ordering, the concentration of aliphatic groups was high as compared to other oxidation conditions. Treatment of Taunit with the HNO3/H2SO4 mixture, on the contrary, increased the number of defects in graphite layers and decreased the concentration of aliphatic structures.

TiO2 (rutile) samples with a hierarchical 3D nanostructure of the particles were synthesized by two methods: liquid hydrolysis of TiCl4 at 90 °С and atmospheric pressure; hydrothermal synthesis from TiCl4 at 160 °С and different [H2O]/[Ti] ratios. The effect exerted by conditions of the synthesis and post-treatments on the crystallite size, morphology, electronic properties and pore structure of the rutile samples was investigated. It was shown that severe hydrothermal conditions with the ratio [H2O]/[Ti] = 20 provide the formation of a more perfect crystal structure of rutile with a smaller band gap energy (3.00 eV against 3.06 eV for the rutile obtained by liquid hydrolysis at atmospheric pressure). The study revealed the stabilizing effect of cerium cations on the pore structure of rutile, which changes upon thermal treatment.

Rutile nanostructures with a 3D hierarchical structure organization are synthesized via the sol-gel technique using TiCl4 as a titanium precursor and HCl to regulate the acidity. The effects the synthesis conditions—molar ratios of the reagents ([Cl–]/[Ti4+] and [H2O]/[Ti4+]) and temperature—have on the mechanism of formation of the rutile phase are established. We show that the texture and morphology of the rutile nanostructrures depend on the particle packing at all levels of the hierarchical organization and are directly related to the synthesis conditions.

The development of efficient and convenient systems for the delivery of nucleic-acid-based drugs into cells is an urgent task. А promising approach is the use of various nanoparticles. Silica nanoparticles can be used as vehicles to deliver nucleic acid fragments into cells. In this work, we developed a method for the synthesis of silicon–organic (Si–NH2) non-agglomerated nanoparticles by the hydrolysis of aminopropyltriethoxysilane (APTES). The resulting product forms a clear solution containing nanoparticles in the form of low molecular weight polymer chains with [─Si(OH)(C3H6NH2)O─] monomer units. Oligonucleotides (ODN) were conjugated to the prepared Si–NH2 nanoparticles using the electrostatic interaction between positively charged amino groups of nanoparticles and negatively charged internucleotide phosphate groups in oligonucleotides. The Si–NH2 nanoparticles and Si–NH2·ODN nanocomplexes were characterized by transmission electron microscopy, atomic force microscopy and IR and electron spectroscopy. The size and zeta potential values of the prepared nanoparticles and nanocomplexes were evaluated. Oligonucleotides in Si–NH2·ODN complexes retain their ability to form complementary duplexes. The Si–NH2Flu nanoparticles and Si–NH2·ODNFlu nanocomplexes were shown by fluorescence microscopy to penetrate into human cells. The Si–NH2Flu nanoparticles predominantly accumulated in the cytoplasm whereas ODNFlu complexes were predominantly detected in the cellular nuclei. The Si–NH2·ODN nanocomplexes demonstrated a high antisense activity against the influenza A virus in a cell culture at a concentration that was lower than their 50% toxic concentration by three orders of magnitude.

Cold gas dynamic spraying was used to obtain coatings based on γ-Al2O3 and Pd-CeO2/γ-Al2O3 catalyst on a stainless steel foil. The coatings were studied by thermal cycling, BET, SEM, TEM, and XPS methods. The textural and adhesion characteristics of the coatings were found to depend on the composition of initial alumina powders with metallic aluminum (weight ratios of the components were varied from 2:8 to 8:2). It was shown that a mixture containing 25% γ-Al2O3 and 75% Al provides the optimal properties of the coatings. The effect produced by a method of the active component introduction into the coating on the catalytic properties of samples was examined. A considerable advantage of Pd introduction by impregnation in the preliminarily sprayed γ-Al2O3 layer over the direct spraying of the finished catalytic composition on the foil was demonstrated.

Nanoscale particles of titanium dioxide with rutile crystal modification are synthesized by the thermolysis of TiCl4 in the presence of HCl. It is found that the temperature regime at certain molar ratios of [H2O]/[Ti] and [Cl]/[Ti] is the key factor which determines the formation of titanium dioxide crystal phases and their proportion in the reaction mixture.

Different types of bleomycins are used extensively in cancer therapy. Antibiotics scarcely penetrate through cell membranes, leading to the necessity of using high concentrations of the drug and, therefore, overall body toxicity. To study the penetration of an antibiotic into cells, the fluorescein residue (Flu) was introduced in bleomycin A5 (Blm) to form BlmFlu. It was shown by confocal fluorescent microscopy that BlmFlu in the presence of titanium dioxide nanoparticles (TiO2, 3–5 nm), in contrast to free BlmFlu, efficiently penetrate the cell cytoplasm. After being delivered into cells in the presence of TiO2, Blm appeared to be 7–10 times more efficient than free Blm in the fragmentation of intracellular nucleic acids. The results suggest that nanoparticles are very promising to promote the delivery of antibiotics into cells, which will allow reducing their therapeutic dose.

Fiber glass supported nanosized Co and Co-Ni catalysts were prepared by solution-combustion synthesis and characterized for their structure and catalytic activity.

Titanium dioxide (TiO2) in a suspension or absorbed on a film possesses bactericidal and virucidal properties caused by photocatalytic reactions. Our electron microscopic examinations showed that titanium dioxide nanoparticles destroyed the influenza virus after 30 min incubation. Virological studies revealed the inactivation of the influenza virus by TiO2, depending on the concentration of nanoparticles and the incubation period. The inactivation effect was observed when the incubation was performed in darkness, unlike the TiO2 suspension. We propose that the virus-inactivation properties of TiO2 are mainly based on the direct contact between nanoparticles and virus particles.

Fe-based catalysts of different geometry are developed for the purification of coke oven gases: bulk, supported on alumina and supported on alumina silicate monoliths. Adsorption and decomposition of H2S on the catalysts developed are studied. Influence of active component content, type of support material and modification by Mn and Mo on the catalyst activity in de-H2S process is elucidated. Supported monolith catalysts show superior activity over bulk and supported spherical catalysts in H2S decomposition reaction and demonstrate stable operation in ammonia decomposition process during 2 hours at 900 °C giving 100% ammonia conversion.

The use of various nanoparticles is a promising way to solve the current problem of drug delivery in medicine and biology. Nanocomposites consisting of titanium dioxide and oligonucleotides noncovalently attached to nanoparticles through the polylysine linker (TiO2 x PL-DNA) have been designed to deliver of DNA fragments into cells. Three forms of TiO2 nanoparticles (amorphous, anatase, and brookite) were used for construction of nanocomposites. The size, morphology, and chemical composition of TiO2 nanoparticles and TiO2 x PL-DNA nanocomposites were characterized. DNA fragments in the proposed nanocomposites were shown to retain their ability to form complementary complexes. TiO2 x PL-DNA nanocomposites independently on the form of nanoparticles were shown by confocal microscopy to penetrate into HeLa cells without any transfection agents and physical impact. The presented type of nanocomposites can be applied in the thriving technology of drug delivery to achieve high therapeutic and biological efficacy.

In this study we examine the possibility that TiO2 nanoparticles and their conjugates can penetrate into cultivated cells without any special transfection procedures. Oligonucleotides and their derivates were conjugated with the TiO2 nanoparticles, which were obtained as colloidal solutions at a concentration of TiO2 0.3M by TiCl4 hydrolysis. The electronic microscopy of various cell cultures (KCT, Vero, and MDCK) treated with nanoparticle solutions (20 µg/µl) showed that nanoparticles could enter the cells and accumulate in the vacuoles and phagosomes and form inclusions in cytoplasm. Thus, we demonstrated the penetration of TiO2 nanoparticles and their oligonucleotide conjugates into intracellular space without any auxiliary operations. Most other researches used electroporation techniques for similar purposes [1, 2, 5].