Кафедра хімії

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4-(N-Boc-амино)-1Н-1,2,3-триазолкарботиоамиды в синтезе производных новой гетероциклической системы [1,2,3]триазоло[4,5-e][1,4]тиазепина
(2021) Сирота, Наталия; Кемский, Сергей; Больбут, Андрей; Чернобаев, Игорь; Лявинец, Александр; Вовк, Михаил
4-(N-Boc-амино)-1Н-1,2,3-триазолкарботиоамиды, полученные последовательной обработкой 4-(N-Boc-амино)-1Н-1,2,3-три- азолов n-BuLi и алкилизотиоцианатами при –78÷–60°C, при действии этилбромацетата образуют соответствующие 4-(N-Boc- амино)-5-тиоимидаты, которые в насыщенном НCl диоксане подвергаются внутримолекулярной циклоконденсации в 8-(алкил- имино)-4,8-дигидро-1Н-[1,2,3]триазоло[4,5-e][1,4]тиазепин-5(6Н)-оны.
Adsorption of proteins on nano-silica modified with antimicrobial drugs
(2019) Gaidai, Alina; Vakuliuk, Polina; Furtat, Iryna; Kunytsia, Natalia; Murlanova, Tatiana; Golub, Alexander
Матеріали конференції "Українська конференція з міжнародною участю "Хімія, фізика та технологія поверхні" та практикум "Біосумісні наночастинки на основі металів: синтез та застосування".
Commercial Silica Materials Functionalized with a Versatile Organocatalyst for the Catalysis Of Acylation Reactions in Liquid Media
(2024) Brand, Raoul; Maass, Mareike; Grebenyuk, Anatoliy; Golub, Alexander; Smarsly, Bernd
Silica materials, natural and synthetic variants, represent a promising material for the application in heterogeneous organocatalysis due to their readily modifiable surface and chemical inertness. To achieve high catalyst loadings, usually, porous carriers with high surface areas are used, such as silica monoliths or spherical particles for packed bed reactors. While these commercial materials were shown to be efficient supports, their synthesis is elaborate, and thus less complex and cheaper alternatives are of interest, especially considering scaling up for potential applications. In this work, two commercial silica materials functionalized with the organocatalyst 4-(dimethylamino)pyridine (DMAP) were used in catalytic acylation reactions: a mesoporous silica gel (Siliabond-DMAP) and non-porous silica nanoparticles (Ludox). While both were successfully used in the acylation of phenylethanol, the latter required significantly longer reaction times, presumably due to the lack of mesopores and the associated spatial confinement, as well as agglomeration that limits the active amount of catalyst. Furthermore, we find that the influence of the linker molecule is negligible, since for two different linker motifs the reaction yields and activation energy remain largely similar. Lastly, as main result the commercial material Siliabond-DMAP, despite the non-uniform particles, were employed in a flow setup, thus demonstrating the potential as support material for application in heterogeneous organocatalysis.
Development of a Catalyst for Flue Gas Purification from Carbon Monoxide of Multi-Chamber Furnaces for Baking Electrode Blanks
(2021) Ivanenko, Olena; Trypolskyi, Andrii; Gomelya, Nikolai; Karvatskii, Anton; Vahin, Andrii; Didenko, Olga; Konovalova, Victoria; Strizhak, Peter
The catalysts based on natural zeolite-clinoptilolite of Sokyrnytsia deposit modified with oxides of Mn4+, Fe2+, Fe3+, Cu2+, Cr3+ were synthesized. It was determined that 100% conversion of carbon monoxide was achieved at a temperature of 390ºC when using the copper-manganese-oxide catalyst (30% CuO + 70% MnO2). It was shown that although the use of the manganese-oxide catalyst provided 92.8% of CO conversion degree, this catalyst had the most advantages for application compared to the other studied solids. The structural parameters of the manganese-oxide catalyst were determined using XRD, SEM, and nitrogen adsorption. The composition of the main elements of the catalyst samples was determined by micro-X-ray spectral analysis. It was shown that using the catalyst containers in chambers heated by flue gases in the fire channels of a multi-chamber furnace for baking of electrode blanks can be one of the constructive solutions to the problem of flue gas purification from carbon monoxide. The environmental safety of the copper-manganese-oxide catalyst application for the treatment of the flue gases of electrode production is justified by obtaining a catalyst from spent sorbents for purification of the manganese-containing natural water and its non-toxicity in the case of burial or storage in landfills.
Development of Antimicrobial Membranes via the Surface Tethering of Chitosan
(2009) Nigmatullin, Rinat; Konovalova, Victoria; Pobigay, Ganna
To render the surface of ultraﬁltration membranes biocidal, cellulose membranes were modiﬁed with chitosan, a naturally occurring polycationic biocide. Through the use of chitosans of different molecular weights and membranes with different pore sizes, the alteration of the morphological structure of tethered chitosan layers was achieved. The importance of such structural differences in the antimicrobial activity of the prepared membranes against gram-positive Staphylococcus aureus and gram-negative Escherichia coli was studied. The antimicrobial efﬁciency improved with the use of chitosans with higher molecular weights and membranes with smaller pore sizes. This suggested that the surface location of the grafted chitosan chains was more preferential for a higher antimicrobial activity of the surface. Membranes modiﬁed with chitosan showed higher antimicrobial efﬁciency against gram-positive S. aureus than against gramnegative E. coli.
Development of the technology and research of hydrogel with the combination of alginate and ethonium for immediate release drug delivery systems
(2024) Sikach, Alina; Konovalova, Viktoriia
The purpose of this study was to develop a technology for obtaining hydrogel systems for the immediate release of drugs and to study the kinetics of the release of a bactericidal drug to facilitate the healing process of open wounds. For this, sodium alginate, partially hydrophobized sodium alginate, anhydrous calcium chloride and sodium carbonate were used.
The effect of nanocomposite, impregnated with ornidazole, on biofilm formation by opportunistic microorganisms
(2019) Lupatsii, M.; Furtat, Iryna; Murlanova, Tatiana; Vakuliuk, Polina; Golub, Alexander
Abstract of the speech at International Research and Practice Conference "Nanotechnology and Nanomaterials" (NANO-2019), 27-30 August 2019, Lviv, Ukraine
Electrolyte-Electrolyte Phase Separation in a DC Magnetic Field
(2017) Gorobets, Yu.; Gorobets, O.; Derecha, D.; Skirta, Yu.; Gerasimchuk, I.; Konovalova, Victoria; Kyba, A.
Presentation speech at the International Research and Practice Conference "Nanotechnology and Nanomaterials" (NANO-2017), 23-26 August 2017, Chernivtsi, Ukraine.
Enhanced transport and antifouling properties of polyethersulfone membranes modified with α-amylase incorporated in chitosan-based polymeric micelles
(2020) Kolesnyk, Iryna; Konovalova, Victoria; Kharchenko, Kateryna; Burban, Anatoliy; Kujawa, Joanna; Kujawski, Wojciech
The objective of this study is related to the modification of polyethersulfone membranes with α-amylase incorporated into chitosan-based polymeric micelles in order to reduce the membrane fouling. Amphiphilic chitosan derivatives have been synthesized through grafting of palmitic (PA) and stearic (SA) acids onto low-molecular weight chitosan. CMC values of palmitoyl and stearoyl derivatives of chitosan are equal to 5.7⋅10 2 mg/mL and 3.9⋅10 2 mg/mL, respectively. Whereas, the size of polymeric micelles amounted to 707 -64 nm and 609 - 57 nm for Chit-g-PA and Chit-g-SA, accordingly. The obtained micelles with enzyme have been adsorbed onto the surface of polyethersulfonic membranes. Modified membranes are characterized by high stability of the coating over time, thanks to the surface-active properties of chitosan derivatives and electrostatic interactions. The antifouling biocatalytic properties of modified membranes were studied in the process of starch filtration. The unmodified membrane showed the lowest permeability with an increase in the concentration of starch solutions due to dramatically increased cake formation. The permeability of modified membranes has been improved remarkably compared to the pristine one during starch ultrafiltration. The cake resistance of modified membranes decreases 6-fold, compared to the unmodified PES one. Furthermore, the effect of concentration polarization is attenuated owing to starch hydrolysis by α-amylase incorporated into polymeric micelles. The maximum activity of α-amylase immobilized on PES membrane is observed in the pH range of 6.5–7.5 and the higher resistance of enzyme to acidic media compared to the native one has been shown. High stability and reusability of immobilized α-amylase has been demonstrated. The degree of starch conversion reduces by 35% and 30% after 10 cycles for a membrane modified with Chit-g-PA and Chit-g-SA, respectively.
Fabrication of polyelectrolyte complexes based on natural polysaccharides for potential drug-delivery systems
(2024) Sikach, Alina; Konovalova, Viktoriia
Polyelectrolyte complexes are materials based on polyelectrolytes with the opposite charge, which, as a rule, are soluble in water. The interaction between polyelectrolytes with the opposite charge leads to the formation of an insoluble substance that can turn into a solid in an aqueous medium. Such a process occurs without the use of organic solvents and is initiated by the dissolution of salt in water, causing the complexation of polyelectrolytes by adjusting pH or salinity.
Fabrication of PSS-PDADMAC membranes via salt dilution-induced aqueous phase separation
(2024) Sikach, Alina; Konovalova, Viktoriia
Polyelectrolyte complex membranes are materials based on oppositely charged polyelectrolytes that are typically soluble in water. Interaction between oppositely charged polyelectrolytes creates an insoluble substance that can form solids in aqueous environments. Such a process does not require organic solvents, and such an aqueous salt-dilution-induced phase separation process induces polyelectrolyte complexation through a pH or salinity switch [1]. Due to the low dielectric constant polyelectrolyte complex membranes are stable in organic solvents, which makes them suitable for a wider range of separation processes [2]. In this study membranes based on poly (sodium 4-styrene sulfonate) (PSS) and poly (diallyl dimethyl ammonium chloride) (PDADMAC) were obtained using the method proposed by J. Kamp et al. [1]. The investigation focused on assessing the impact of polymer concentration and forming knife thickness on the membrane properties.
Fe2+ Removal from Water Using PVDF Membranes, Modified with Magnetite Nanoparticles, by Polyelectrolyte Enhanced Ultrafiltration
(2018) Konovalova, Victoria; Kolesnyk, Iryna; Ivanenko, Olena; Burban, Anatoliy
The aim of this study was to show results of Fe2+ removal from water by polyelectrolyte enhanced ultrafiltration on polyvinylidene fluoride membranes modified with magnetite nanoparticles. Magnetite nanoparticles were synthesized by the co-precipitation method and stabilized with sodium polyacrylate. At first stage, the surface of PVDF membranes was modified by grafting of polyethylenimine. At the second stage the polyelectrolyte, grafted to the membrane surface, was used as a linker for magnetite nanoparticles immobilization. The modification of membranes was confirmed by IR spectroscopy, scanning electron microscopy and electro kinetic analysis. The dependence of zeta-potential on pH for PVDF membrane modified with PEI has confirmed the modification of the membrane surface as zeta-potential increases with pH decrease. SEM has shown that the surface of modified membrane is densely covered with nanoparticles, which form clusters. The dependence of the volumetric flux on the applied pressure at various concentrations of the carboxymethylcellulose (CMC) has been studied. Polyelectrolyte enhanced ultrafiltration with CMC has been used for iron(II) removal at initial Fe2+ concentration of 20 mg/L. The concentrations of iron(II) in permeate using an unmodified membrane has ranged from 0.6 to 1.0 mg/L, whereas for the modified membrane it has been 0.02÷0.08 mg/L.
Formation Of PSS-PDADMAC Membranes Based On Salt Dilution-Induced Aqueous Phase Separation
(2023) Sikach, Alina; Konovalova, Viktoriia
In these study membranes based on Poly (sodium 4-styrene sulfonate) (PSS) and Poly (diallyl dimethyl ammonium chloride) (PDADMAC) were obtained by the method proposed by J. Kamp et al. [1]. The membrane preparation is based on interpolymer complexes formation in a water medium. The influence of the concentration of polymers (20 and 25 wt. %) and the thickness of the forming knife (200 and 400 μm) on the morphological properties of the formed membranes were studied. It was established that the average pore size for membranes based on 25% solutions is higher (107 ± 4 nm) than for 20% solutions (94 ± 3 nm). The pore structure in the samples is spongy (Fig.1) and does not depend on concentration or thickness.
Functional nanoparticles for biomedical applications: a dsc study of membranotropic behavior
(2021) Samoilov, A.; Lisetski, L.; Kasian, N.; Losytskyy, M.; Golub, Alexander; Yashchuk, V.
Interaction of fullerene-containing silica nanoparticles (SiO2—С60, SiO2—С60—Pd) and DNA of natural origin (DNA and low molecular weight DNA - LmwDNA) with phospholipid model membranes was studied using differential scanning calorimetry (DSC). SiO2—С60, SiO2—С60—Pd and DNA had only minor effects on L-a-dipalmitoyl phosphatidyl choline (DPPC) membrane phase transitions, remaining essentially inert. LmwDNA induced noticeable changes in the DSC profiles, with the effects (increasing of the main phase transition temperature, significant peak broadening and splitting, vanishing of the pre-transition peak) increasing with concentration. No noticeable deviations from additivity could be noted under joint introduction of the nanosystems into DPPC membranes. Keywords: nanoparticles, phospholipid membranes, differential scanning calorimetry, low molecular weight DNA, phase transition.
High-temperature hybrid phthalonitrile/amino-MMT nanocomposites: Synthesis, structure, properties
(2019) Bershtein, Vladimir; Fainleib, Alexander; Yakushev, Pavel; Kirilenko, Demid; Gusakova, Kristina; Markina, Daria; Melnychuk, Oleksandr; Ryzhov, Valery
Hybrid nanocomposites based on heterocyclic network, obtained from bisphenol A based phthalonitrile (BAPhN) with different (0.03–5.0 wt%) contents of reactive amino-montmorillonite (MMT) nanolayers, were synthesized and studied for the first time. Their structure, dynamics, thermal, relaxation and elastic properties were characterized using transmission electron microscopy (TEM), mid-infrared (mid-IR), far-infrared (far-IR) and energy dispersive X-ray (EDX) spectroscopies, differential scanning calorimetry (DSC), and by dynamic mechanical analysis (DMA) and thermogravimetry (TGA) measurements performed in both air and nitrogen mediums at temperatures from 20 to 600–900°C. Depending on nanofiller content, different extents of MMT stacks exfoliation, from single nanolayers to MMT stacks with tens nanolayers-thickness, are observed in the nanocomposites. The pronounced dynamic heterogeneity in the glass transition and the ‘constrained dynamics’ effects are shown. For the pristine matrix, Tg (DMA) = 446 °С varying from 460 to 570 °С for the nanocomposites. After high-temperature treatment in N2 medium, the relaxation spectrum and glass transition disappear, and constant dynamic modulus E′ ≈ 3 GPa at 20–600°С is registered. A satisfactory thermal stability of the nanocomposites, with retaining the sample integrity is observed at temperatures up to ~500 °C in air and up to 900 °C in N2 medium.
Hybrid antibacterial nanocomposites based on silica
(2017) Kotsyuda, S.; Vakuliuk, Polina; Furtat, Iryna; Lebed, A.; Bilyayeva, O.; Golub, A.
Nanocomposites with biological activity is gaining a big interest in the field of nanomedicine as this capacity plays crucial role in beneficial or adverse effects of a drug or working substance on living matter.
Hydrogel films based on modified alginate as a base for personalized antibacterial wound treatment
(2023) Sikach, Alina; Konovalova, Viktoriia
Materials based on natural polysaccharides are increasingly used for innovative wound dressings which have more extensive requirements that current medical products on the market cannot provide [1]. The issue of open wounds treatment became crucial in Ukraine due to the ongoing war, necessitating wound dressings that provide mechanical, antibacterial protection, and accelerate healing process. In this work, ethonium-containing hydrogel films were developed using partially hydrophobized alginate (AlgM) unmodified alginate (Alg) and 1:1 mixture of Alg and AlgM (Alg+AlgM). These films were studied to determine the effect of alginate modification on ethonium release kinetics.
Hydrogel films based on sodium alginate modified with octane-1-amine: enhanced pore formation and potential
(2024) Sikach, Alina; Konovalova, Viktoriia; Kolesnyk, Iryna
The use of wound dressings is gaining more and more popularity, especially in the field of tactical and military medicine. Developing wound dressings capable of facilitating wound treatment and reducing healing time is one of the challenges of modern science. So, sodium alginate (Alg) is a good candidate for the development of wound dressings due to its bio- and hemocompatibility and biodegradability. However, Alg has its shortcomings, which can be dispatched by modification. The purpose of this work was to investigate the effect of Alg modification on the kinetics of ethonium release from crosslinked with Ca2+ ions samples. For this purpose, a method of Alg modifying with octane-1-amine was developed without the use of organic solvents and with the use of 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride (EDCl) as an initiator. The optimal parameters of alginate modification process were defined as 60 °С temperature and 24 hours duration. Physicochemical methods confirmed the success of the modification. Films based on the alginate modified with octane-1-amine (AlgM) were obtained using a calcium chloride solution as a crosslinker. The kinetics of swelling was studied and we found that the degree of swelling of the sample based on AlgM after 10 minutes is twice as large (α = 0.71) as for Alg (α = 0.37), which indicates a faster release of drugs. It has been found that the kinetics of release of ethonium depends not only on the kinetics of swelling but also on the chemical nature of the drug. The ethonium was immobilised in alginate films as a model of bactericidal drug. The kinetics of ethonium release was studied at different pH values corresponding to the pH of healthy skin (5.5), open wounds (7.2) and inflamed wounds (8.2). It was found that the release of ethonium from the sample based on AlgM is more pH-sensitive and prolonged, compared to the sample based on Alg. This effect is explained by the appearance of an additional mechanism of retention of ethonium by AlgM due to hydrophobic-hydrophobic interactions in the films. The prolonged release properties observed in the drug-loaded samples make them promising candidates for the development of targeted drug delivery systems and wound dressings, which are particularly relevant for the treatment of chronic and burn wounds. Future research will focus on optimizing the crosslinking method and exploring potential applications of modified alginate-based materials in biomedical sciences.
Hydrogen peroxide decomposition by kaolin clay modified with nanoceria
(2019) Grinko, Alina; Brichka, A.; Bakalinska, O.; Kartel, Nikolay
Матеріали конференції "Українська конференція з міжнародною участю "Хімія, фізика та технологія поверхні" та практикум "Біосумісні наночастинки на основі металів: синтез та застосування".
Immobilization of antibacterial agents on the surface of cellulose membranes modified with polyglycedylmethacrylate
(2009) Chyketa, Olga; Pobigay, Ganna; Konovalova, Victoria; Burban, Anatoliy
A new method of glycidylmethacrylate (GMA) radical copolymerization on the surface of commercial cellulose membranes followed by immobilization of synthetic antibiotics on grafted poly(GMA) chains has been developed. Transport and antimicrobial properties of modified membranes have been studied. It has been shown that decreasing of samples permeability is caused by grafting of GMA, and it depends on initiator concentration, duration of reaction and process temperature. Infrared spectrometry and capillary electrophoresis were used to analyze modified samples. Antibacterial properties of membranes modified by nalidixic acid and levofloxacin were studied against gram-negative bacteria E. coli and gram-positive bacteria S. aureus. Higher antibacterial activity of membranes modified by levofloxacin in comparison to those modified by nalidixic acid was shown. Thus, antibacterial activity of membranes modified by 0,5% solutions of antibiotics was 90% for samples with nalidixic acid and 100% for samples with levofloxacin. All samples showed lower antibacterial activity against gram-negative bacteria. The antibacterial activity remained stable for 36 days of membrane operation.

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