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Item 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, Михаил4-(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.Item Adsorption of proteins on nano-silica modified with antimicrobial drugs(2019) Gaidai, Alina; Vakuliuk, Polina; Furtat, Iryna; Kunytsia, Natalia; Murlanova, Tatiana; Golub, AlexanderМатеріали конференції "Українська конференція з міжнародною участю "Хімія, фізика та технологія поверхні" та практикум "Біосумісні наночастинки на основі металів: синтез та застосування".Item Antibacterial properties of composite materials based on metal/metal-oxide nanoparticles, nanosilica and polylactid acid(2025) Bespalko, Oleksandr; Vakuliuk, Polina; Furtat, Iryna; Pryshchepa, Oleksandra; Kozakevych, Roman; Pomastowskі, PawełThe global rise in antimicrobial resistance necessitates the development of alternative materials with effective antibacterial properties. This study compares two classes of nanocomposites: silver nanoparticle (AgNP)- and zinc oxide (ZnO)-based systems, both immobilized on silica (SiO₂) and treated with polylactic acid (PLA) to enhance biocompatibility and biodegradability. AgNP-containing composites (SiO₂- Ag and SiO₂-Ag-PLA) exhibited potent, broad-spectrum antibacterial activity, particularly against Gram-negative E. coli and K. pneumoniae, though activity decreased when modified with PLA—likely due to reduced ion release and surface coverage interference.Item Antibacterial properties of silver-containing composite materials based on silica and polylactic acid(2025) Bespalko, Oleksandr; Vakuliuk, Polina; Furtat, Iryna; Pryshchepa, Oleksandra; Kozakevych, Roman; Pomastowskі, PawełThis study aimed to investigate composite materials containing silver nanoparticles (AgNPs) impregnated on silica (SiO2) and incorporated into a polylactic acid (PLA) matrix.Item Antibacterial properties of zinc oxide-containing composite materials based on silica and polylactic acid(ЛНУ імені Івана Франка, 2025) Bespalko, Oleksandr; Vakuliuk, Polina; Furtat, Iryna; Pryshchepa, Oleksandra; Kozakevych, Roman; Pomastowski, PawełAntimicrobial resistance poses a critical threat to global health, as conventional drugs increasingly fail against multidrug-resistant pathogens. A key challenge lies in the inability of many antimicrobials to penetrate microbial membranes or act effectively against intracellular infections. Nanoparticles (NPs) offer a promising alternative due to their unique physicochemical properties and broad-spectrum antimicrobial activity. Among these, zinc oxide nanoparticles (ZnO NPs) are especially notable for their low cytotoxicity and effectiveness against resistant strains.Item Commercial silica materials functionalized with a versatile organocatalyst for the catalysis of acylation reactions in liquid media(2025) Brand, Raoul; Maass, Mareike; Grebenyuk, Anatoliy; Golub, Alexander; Smarsly, BerndSilica 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.Item Dependence of the catalytic properties of rGO-Al2O3 nanocomposites on the fraction size of aluminum oxide carrier(2025) Nosach, Viktoriia; Buchko, I.Carbon nanomaterials catalyze hydrogenation with molecular hydrogen, as demonstrated in hydrocarbon hydrogenation [1]. Their catalytic activity requires high crystallinity and low oxygen content [2]. Given its crystallinity and large surface area, reduced graphene oxide (rGO) is a promising hydrogenation catalyst. However, the effects of graphene plane size, layer count, defectiveness, and carrier structure on rGO’s activity remain unclear. This study investigates the catalytic properties of rGO applied to aluminum oxide and the impact of different carrier size fractions on nanocomposite activity.Item 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, PeterThe 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.Item Development of Antimicrobial Membranes via the Surface Tethering of Chitosan(2009) Nigmatullin, Rinat; Konovalova, Victoria; Pobigay, GannaTo 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.Item 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, ViktoriiaThe 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.Item Effect of nanoceria calcination on the effective activation energy of the hydrogen peroxide decomposition reaction it catalysed(2025) Hrynko, A.; Brichka, A.; Bakalinska, Olha; Oranska, O.; Kaleniuk, Н.; Kartel, M.The aim of this work is the preparation of nanoceria samples; calcination it at different temperatures; characterization its properties; establishing the effect of nanoceria calcination on the effective activation energy of the hydrogen peroxide decomposition reaction which it catalysed.Item The effect of nanocomposite, impregnated with ornidazole, on biofilm formation by opportunistic microorganisms(2019) Lupatsii, M.; Furtat, Iryna; Murlanova, Tatiana; Vakuliuk, Polina; Golub, AlexanderAbstract of the speech at International Research and Practice Conference "Nanotechnology and Nanomaterials" (NANO-2019), 27-30 August 2019, Lviv, UkraineItem 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.Item 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, WojciechThe 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.Item Exploring alginate-chitosan polyelectrolyte complex matrices for smart drug release applications(ЛНУ імені Івана Франка, 2025) Sikach, Alina; Konovalova, ViktoriiaThis study is aimed at developing a controlled method for the formation of PECs for drug immobilization in delivery systems based on Alginate as polyanion and Chitosan as polycation (AC complexes).Item Fabrication of polyelectrolyte complexes based on natural polysaccharides for potential drug-delivery systems(2024) Sikach, Alina; Konovalova, ViktoriiaPolyelectrolyte 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.Item Fabrication of PSS-PDADMAC membranes via salt dilution-induced aqueous phase separation(2024) Sikach, Alina; Konovalova, ViktoriiaPolyelectrolyte 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.Item Fe2+ Removal from Water Using PVDF Membranes, Modified with Magnetite Nanoparticles, by Polyelectrolyte Enhanced Ultrafiltration(2018) Konovalova, Victoria; Kolesnyk, Iryna; Ivanenko, Olena; Burban, AnatoliyThe 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.Item Formation Of PSS-PDADMAC Membranes Based On Salt Dilution-Induced Aqueous Phase Separation(2023) Sikach, Alina; Konovalova, ViktoriiaIn 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.Item 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.