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Screen-printed Potentiometric Sensors for Cefuroxime Axetil Determination in Small Sample Volumes

Authors: Kulapina E. G., Kulapina O. I.

Potentiometric screen-printed cefuroxime axetil sensors were developed. The optimum membraneand carbon ink compositions were determined. The main sensor electroanalytical and operational characteristics were evaluated. The sensors were used to determination of cefuroxime axetil in small sample volumes of model water solutions and mixed saliva (oral fluid). Upgrading sensor designs opens up new sensor application for pharmaceutical kinetic antibiotic studies on the mixed saliva analysis and correction treatment of various pathological processes.

Chemometric Method of PLS in the Treatment of Titrimetric Data when Opredeleniye of Arginine and Lysine in Mixed Solutions

Authors: Chernova R. K., Monakhova Y. B., Varygina O. V.

Arginine and lysine are the most important α-amino acids that are part of many proteins, which play an important role in the processes of nitrogen metabolism, growth and restoration of body tissues. It is used in medical nutrition in the postoperative recovery period, as well as as diagnostic factors. The simple express methods of separately determining the main α-amino acids of arginine and lysine in their mixed solutions are in demand.

Antioxidant Status of Macrobasidiomycetes Mycelium Grown in the Presence of Organoselenium Compounds

Authors: Pankratov A. N., Tsivileva O. M., Tsymbal O. A., Beloborodaya А. S., Drevko Y. B.

Antioxidant status maintenance plays a significant role for mushroom cultures in respect to oxidative stress resistance, cytodifferentiation and transition to the generative stage. Strong antioxidants are the selenium compounds. One of the antioxidant action indices is the antiradical activity determined by means of the spectrophotometric method using the reactions with the free radical 1,1-diphenyl-2-picrylhydrazyl (2,2-diphenyl-1-picrylhydrazyl, N,N-diphenyl-N’-picrylhydrazyl, DPPH) (C6H5) 2N– N•–C6H2(NO2) 3-2,4,6.

Equilibrium Liquid–Liquid–Solid and Critical Phenomena in the Quaternary System Cesium Nitrate+Water+Pyridine+Butyric Acid with in the Range of 5 to 60°C

Authors: Smotrov M. P., Chepurina Z. V., Kurskii V. F., Cherkasov D. G.

Phase equilibria and critical phenomena in the component mixtures of a cut of the composition tetrahedron of the quaternary system cesium nitrate + water + pyridine + butyric acid were studied in the range of 5–60°C by the visual-polythermic method. The phase equilibria in the component mixtures were studied using sections of one cut of the composition tetrahedron. The cut position was chosen in such a way as to cross all figures of the phase states with the presence of a solid phase in order to observe the phase behavior of the monotectic state figure as temperature changes.

Luminescent Properties of Doxycycline in the Presence of Silver Nanoparticles Modified by Ions of Europe

Authors: Smirnova T. D., Zhelobitskaya E. A., Danilina T. G.

Fluorescence spectroscopy is a routine tool for studying cellular and molecular visualization, flow cytometry, medical diagnosis, forensic medical examination, genetic analysis, and also an analytical method. However, most available organic dyes used to produce an optical signal have a number of important limitations, such as hydrophobicity, low quantum yield, and low photostability.

On Interaction of Synthetic Food Dye E133 with Cetylpiridinium Cations

Authors: Strelkova К. V., Varygina O. V., Chernova R. K., Koblova О. Е., Kostritsky A. Y.

Synthetic food colorings (SPK) are widely used to impart consumer properties to food. But. many of them are allergens. Therefore, their definition in food objects is relevant. The rapid method of determining the SPK is ionometry. It is based on the use of ion- selective electrodes. Such an electrode for determining the food coloring E133 is not described in the literature. The purpose of this work is the study of the ionophore. Used to determine the E133 in a variety of food products.

Phase Equilibria in the Ternary System “Potassium Iodide – Water – Tert-Butyl Alcohol” within 5–30°C

Authors: Varlamova Т. М.

Studying of the influence of the salt nature and temperature on the liquid-liquid equilibrium in the ternary systems “salt – binary solvent” is topical for the development of the salting-in–salting- out theory. In addition, the ternary potassium iodide-water-alcohol systems are constituents of the quaternary iodine – potassium iodide – water – alcohol ones, studying of which is of practical interest in terms of determining the mixed solvent compositions with the highest iodine-dissolving power.

Phase Equilibrium for the System KH2PO4 – K2SO4 – H2O at 25°С

Authors: Кistanova N. S., Korotkikh S. А.

Potassium dihydrogen phosphate is widely used in industrial and agri- culture. The solvent extraction method for producing KH2PO4 from the more cheap extraction phosphoric acid and potassium chloride has gained growing attention recently. To evaluation influence SO42– on the crystallization KH2PO4 it is nessesary comprehensive knowledge of the phase equilibria in the system K+// H2PO42–, SO42– – H2O. The ternary system KH2PO4 – K2SO4– H2O was determined at 25 °C by the improved isothermal method of section.

Transformation of a Stable Catalyst of Catalytic Riforming Facility with Using the Catalyst R-98

Authors: Aniskova Т. V., Romadenkina S. B., Kuzmina R. I.

One of the most important tasks of modern refineries is the modernization of existing plants to increase production and improve the quality of the commodity. In this connection, the catalytic activity of the industrial catalyst of the reforming pro- cess R-98 (containing in its composition platinum and rhenium, in the amount of 0.25% by weight of each) in the conversion of a stable catalyst was studied. Stable catalyst is released from the stabilizer column of the catalytic reforming unit.

Synthesis and Ways of Formation of Hydroxyphenyl Substituted Benz[4,5]imidazole-1,2,3,4,5,6- hexahydro[1,2-a]quinazolines

Authors: Ivonin M. A., Krivenko A. P., Abdulhamid H. A., Krivenko A. P., Ivonin M. A., Sorokin V. V.

To synthesize new potentially biologically active benzimidazoloquinazolines, a three-component condensation of 2-aminobenzimidazole, cyclohexanone and hydroxylatedbenzaldehydes was studied. The reaction proceeds regioselectively when the equimolar ratios of the reagents are boiled for 3 hours in N,N-dimethylformamide and is accompanied by the formation of ortho-phenyl substituted hexahydrobenz[4,5]imidazolo [1,2-a]quinazolines having an angular articulation of the rings and a different number and position of hydroxyl groups in the phenyl substituent.

Qualitative and Quantitative Estimation of Intramolocular Hydrogenic Communication in a Row of Orto-R-phenyl-substituted Tetrazolohexahydroquinazolines

Authors: Vasilkova N. O., Aniskov A. A., Krivenko A. P.

The onе-pot interaction of C-aminotetrazole, cyclohexanone and o-R-benzaldehydes (in contrast to unsubstituted benzaldehyde benzaldehyde) leads to the formation of additionally linear tetrazohexahydroquinazolines, their isomers with an angular articulation of the rings. The appearance of isomers with angular articulation of the rings can be explained by the total influence of the spatial and electronic effects, and the influence of the low-energy interaction by the type of hydrogen binding NH ··R (VVS) can not be ruled out.

Electroanalytical Properties of Non-modified and Polyaniline Modified Solid Contact Cefazolin Selective Sensors

Authors: Kulapina E. G., Kulapina O. I., Dubasova A. Е.

Cefazolin is a cephalosporin antibiotic of the third generation. It is widely used in medical practice for the therapy of various infectious-somatic pathologies. The work was aimed at the creation of solid-contact potentiometric cefazolin-selective sensors. For the first time, polyaniline was used to stabilize the potentials of solid-contact sensors. As the membranes active components, the compound of tetradecylammonium (TDA) with the silver (I) – cefazolin complex were applied.

Sorbents Based on Natural Bentonites, Modified by Polyhydroxocationes Zirconium(IV), Aluminum and Iron(III) by the «Coprecipitation» Method

Authors: Nikitina N. V., Fartukova E. V., Kazarinov I. А., Nikitina N. V.

Presently, the bentonite clays are the popular materials which used in the adsorption refining. The bentonite is characterized by the extensive surface, the high mechanical strength, also it is the cheap and affordable material. In comparison with another cheap natural sorbents, the bentonites are differenced by the high sorption capacity towards to the anions of the various salts. However, the natural bentonite undergoes modification for more effective purification.

Properties, Soil Degradation and Fitotoxicity of Starch Composites with Polyvinyl Alcohol

Authors: Malinkina О. N., Shipovskaya A. B., Grebenyuk L. V., Stepanov M. Y., Papkina V. Y.

Composite films were obtained from a mixture of starch, polyvinyl alcohol, and a plasticizing additive based on aspartic acid. The surface morphology, structural features of the composites, and their behavior in a polythermic mode were studied by scanning electron microscopy, X-ray diffractometry, IR spectroscopy, differential thermal and thermogravimetric analysis. Only carbon dioxide was detected in the gaseous products of thermal decomposition of the samples. The sorption and physico-mechanical properties of our composite films were analyzed.

Polymeric Sorbents for the Collection of Oil and Oil Products from the Surface of Reservoirs: a 2000–2017 Review of the English-language Literature (Part 1)

Authors: Shmakov S. L., Bayburdov T. А.

The scientific literature in English for 2000–2017, devoted to the problem of the development of sorbents based on polymeric materials, intended for collecting spilled oil and oil products from the surface of reservoirs, has been scanned and analyzed. Three most numerous classes of polymeric sorbent materials (cellulosic materials, acrylate copolymers and synthetic rubbers) have been identified, and the oil sorbents proposed are characterized. Prospects of using sorbents of these classes for cleaning up the surface of reservoirs from oil spills are discussed.

Synthesis and Functionalization of Magnetite Мagnetic Nanoparticles with Сhitosan

Authors: Kazimirova K. O., Shtykov S. N.

Superparamagnetic magnetite nanoparticles (MNP) have gained much attraction from the beginning of 21century because of its potential applications in biology, medicine, theranostics, physics, chemistry and chemical analysis due to unique multifunctional properties, including small size, superparamagnetic behavior, low toxicity, high adsorption properties used for magnetic solid-phase extraction (MSPE) in water purification and chemical analysis.

Quantum-chemical Studies of Several Lanthanide Compounds with Products of Starch Thermal Decomposition

Authors: Dzharlagasova D. N., Zakharova T. V., Pozharov M. V.

Lanthanide complexes with organic ligands (including hydrocarbons) find application in medicien as luminescent biomarkers for various pathogenic bacteria. At the same time, starch (as a polysaccharide) can serve as a source for carbon nanoparticles (via thermal decomposition) that have very intensive and longliving luminescence, thus such nanoparticles conjunctioned with lanthanides may be used to create more effective medical probes.

Features of the Reactions of n-hexane on the Catalyst NH4(ZHM)

Authors: Komarova N. I., Taraskin M. O., Aniskova Т. V.

The process of catalytic reforming remains one of the main processes of the modern petrochemical industry, allowing for obtain commodity products – gasoline, with high detonation resistance and raw materials for the petrochemical industry – aromatic hydrocarbons. One of the most important tasks of improving the reforming process is the development of new efficient catalytic systems that don’t have noble metals in their composition.

Polymeric Sorbents for the Collection of Oil and Oil Products from the Surface of Reservoirs: a 2000–2017 Review of the English-language Literature (Part 2)

Authors: Bayburdov T. А., Shmakov S. L.

Oil spills after tanker and pipeline accidents pose a serious threat to the environment, lead to the loss of energy carriers and severely pollute seawater. Mechanical extraction by sorption mechanism is an effective means of oil spill liquidation from the surface of reservoirs. The English 2000–2017 scientific and technical literature devoted to the design of sorbents based on polymeric materials for the collection (absorption) of spilled oil and oil products from the surface of reservoirs with the possibility of subsequent recovery of the useful product was searched and analyzed.

Physico-mechanical Properties of Silicon-chitosan-containing Glycerohydrogels Plates Based on Chitosan L- and D-ascorbates

Authors: Zhuravleva Y. Y., Malinkina О. N., Golyadkina A. A., Shipovskaya A. B., Gegel N. O.

Silicon-containing glycerohydrogel thin-film plates based on chitosan L- and D-ascorbates were obtained by means of biomimetic sol-gel synthesis using silicon tetraglycerolate as a biocompatible precursor. Their stress–strain characteristics were studied. For all the samples of our glycerohydrogel plates, stress–strain curves were recorded, characteristic of soft plastic polymeric materials not reaching their yield point under tensile conditions. At rupture, the material shows some characteristic signs of macroscopic plasticity.

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