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Papers by nataliya kutsevol

Chemical Engineering of Polymers, 2017

Two series of Dextran-graft-Polyacrylamide copolymers with polysaccharide backbone having differe... more Two series of Dextran-graft-Polyacrylamide copolymers with polysaccharide backbone having different molecular weights (Mw = 20 000 and Mw = 70 000) and long grafted Polyacrylamide chains were synthesized by radical copolymerization using Ceric-ion-induced redox initiation. A certain fraction of ionic sites was introduced into the PAA grafts by alkaline hydrolysis during different time periods (NH2 groups were changed by OH groups) in order to convert D-g-PAA into polyelectrolyte. It was established that D-g-PAA copolymers both in non-ionic and in ionic form can adsorb transition metal ions from aqueous solution. These copolymers have high flocculation efficiency due to their expanded conformation in water solution. The flocculation ability is inversely related to the spacing of the PAA grafts (i.e. the length of backbone between the grafts).

Molecular Crystals and Liquid Crystals, 2007

ABSTRACT makes every effort to ensure the accuracy of all the information (the "Cont... more ABSTRACT makes every effort to ensure the accuracy of all the information (the "Content") contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content.

Journal of Molecular Liquids, 2017

Uncharged and anionic copolymers Dextran-graft-Polyacrylamide (D-g-PAA) and linear PAA of similar... more Uncharged and anionic copolymers Dextran-graft-Polyacrylamide (D-g-PAA) and linear PAA of similar molecular weight were tested as flocculants in model kaolin polydisperse suspensions (C = 3 g/dl) having high content of particles less than 2 μm in size (more than 60%) which are difficult to settle down. The flocculation process was characterized by suspension sedimentation rate and degree of supernatant clarification. Dependence of flocculation on the degree of branched copolymers compactness as well as the degree of hydrolysis of the amide groups in the polymers was investigated. The main regularities of selection of suitable branched flocculants based on D-g-PAA and optimal their concentration for effective flocculation process was obtained. It was shown that D-g-PAA in ionic form with the lower grafting efficiency and long PAA grafts ensured the highest degree of supernatant clarification and the highest rate of the suspension sedimentation.

AIP Conference Proceedings, 2008

ABSTRACT Branched polymers Dextran-graft-Polyacrylamide and Dextran Sulphate-graft-Polyacrylamide... more ABSTRACT Branched polymers Dextran-graft-Polyacrylamide and Dextran Sulphate-graft-Polyacrylamide copolymers with long polysaccharide backbone and various amount and length of PAA-grafts were synthesised by radical polymerization using Ce(IV)/HNO3 redox system. It was established, that these copolymers have expanded conformation in solution and are able to intramolecular structure formation. Grafting efficiency is conditioned by amount of initiator and Dextran (or Dextran Sulphate) conformation in solution. It was shown that increase in content of copolymer Polyacrylamide component in Dextran Sulphate-graft-Polyacrylamide copolymers causes decrease in size of macromolecule due to blocking of polyion charge of main polysaccharide chain by counterions.

Nanoscale Advances

The development of precision cancer medicine relies on novel formulation strategies for targeted ... more The development of precision cancer medicine relies on novel formulation strategies for targeted drug delivery to increase the therapeutic outcome.

Polymer, 2006

Copolymers obtained by grafting polyacrylamide (PAA) onto polydextran (DEX) have been synthesised... more Copolymers obtained by grafting polyacrylamide (PAA) onto polydextran (DEX) have been synthesised by ceric-ion-reduced redox initiation method. These copolymers have been characterized by light scattering, self-exclusion chromatography and viscometry in aqueous solutions. The short range molecular structure has been studied by small-angle X-ray scattering. From these results it is suggested that close to the anchoring point the grafted chains are extended while they take on a random conformation far from this point. A few investigations have been carried out in water/DMF (dimethyl formamide) mixtures. It is observed that the molecular weight depends strongly on the dimethyl formamide fraction. These results are discussed by contemplating the existence of PAA/DMF complexes.

Brazilian Journal of Physics, 2006

Micron-sized spheres of mesoporous styrene-divinylbenzene (Sty-DVB) copolymer were produced by su... more Micron-sized spheres of mesoporous styrene-divinylbenzene (Sty-DVB) copolymer were produced by suspension polymerisation in the presence of inert diluents. Using these mesoporous microspheres as a template, optically stable CdS nanoparticles have been synthesized. To characterize these CdS nanoparticles, Raman spectroscopy and micro-photoluminescence were used. We have observed enhanced emission and lasing action at certain wavelengths that correspond to the whispering gallery (WG) modes of the microspheres. High optical stability and low threshold value make this optical system promising in microlaser applications.

Molecular Crystals and Liquid Crystals

Abstract Hydrogel absorbents were synthesized based on cross-linking of Polyacrylamide grafted on... more Abstract Hydrogel absorbents were synthesized based on cross-linking of Polyacrylamide grafted on Dextran or Dextran sulfate sodium salt. It was found that the swelling capacity of hydrogels depends on cross-linker concentration as well as Dextran component. FT-IR studies of hydrogels were carried out to analyze its structure. Methylene blue dye as model cationic medical drug was applied for the absorption/desorption study. Hybrid hydrogels prove the mechanism of absorption by the formation of charged polyelectrolyte/dye complexes. The kinetic model of pseudo-first order was applied to determine the rate constant k of the reaction between hydrogels and dye in the solution.

Springer Proceedings in Physics, 2021

Chemical Engineering of Polymers, 2017

Molecular Crystals and Liquid Crystals, 2021

Abstract Methylene blue as photosensitizer was used for antimicrobial photoinactivation of Staphy... more Abstract Methylene blue as photosensitizer was used for antimicrobial photoinactivation of Staphylococcus aureus in suspension. The antimicrobial activity of methylene blue was activated by red light of low energy density. Determination of CFU in bacterial suspensions was performed in the Goryaev chamber after staining an aliquot of the suspension with Acridine orange. A reduction of CFU/mL of S. aureus to 60% was achieved. The study of antibacterial efficacy of laser light with wavelengths (λex) of 390, 460 and 660 and different energy density against wild strains of S. aureus was carried out for comparison.

Branched nanostructured copolymers dextran-g-polyacrylamide (D-g-PAA) in uncharged and anionic fo... more Branched nanostructured copolymers dextran-g-polyacrylamide (D-g-PAA) in uncharged and anionic form were synthesized, characterized, and tested for flocculation in comparison with linear PAA. The polymers differed in the conformation of grafted polyacrylamide chains determining the molecular compactness. Kaolin clay dispersion with a high content (more than 60%) of particles less than 2 μm in size, which settle down with difficulty, was used as a model system. It was shown that branched copolymers exhibited high flocculation activity in noncharged and ionic forms. In contrast to linear polymers, not only the size of the macromolecule polymer flocculants but also their molecular nanostructure affected the parameters (sedimentation rate and degree of supernatant clarification) of the flocculation process. The degree of supernatant clarification for branched polymers at optimal flocculant concentrations was higher than for linear PAA. Branched and linear flocculants in anionic form wer...

Springer Proceedings in Physics, 2019

The comparative refractive index analysis for two systems, Au sol synthesized into solution of de... more The comparative refractive index analysis for two systems, Au sol synthesized into solution of dextran-graft-polyacrylamide (D-g-PAA) starlike copolymer and solution of D-g-PAA under laser illumination, has been carried out. It was established that Au nanoparticles (AuNPs) are 1.5–6 nm in size. The size of individual polymer molecule in solution was equal to 50–60 nm. Au/D-g-PAA nanosystem was successfully used as nanocarrier for photodynamic anticancer therapy.

Springer Proceedings in Physics, 2019

Poly-N-isopropylacrylamide (PNIPAAm) is a biocompatible thermosensitive polymer that is promising... more Poly-N-isopropylacrylamide (PNIPAAm) is a biocompatible thermosensitive polymer that is promising for use in nanobiotechnology applications since this polymer has a phase transition temperature (LCST) in the physiological temperature range. LCST can be regulated by changing the hydrophilic-hydrophobic balance of the PNIPAAm-containing macromolecule or by changing its structure. The radical copolymerization method was used for the synthesis of the starlike copolymers with dextran core of various molecular weights and with various amounts of grafted dextran-poly-N-isopropylacrylamide (D-PNIPAAm) chains. It was shown that reducing the distance between PNIPAAm grafts affects the conformational transition characteristics of the polymer.

Applied Nanoscience, 2021

The hydrogels based on cross-linked dextran-graft-polyacrylamide (D-g-PAA) and polyacrylamide (PA... more The hydrogels based on cross-linked dextran-graft-polyacrylamide (D-g-PAA) and polyacrylamide (PAA) with different densities of chemical cross-links were synthesized by radical polymerization. They were used as nanoreactors for the photochemical synthesis of silver nanoparticles (AgNPs). The polymer hydrogels and nanocomposites with loaded AgNPs were characterized by SEM, FTIR- and UV–Vis spectroscopy. Swelling studies demonstrated differences in the internal structure of the cross-linked D-g-PAA and PAA samples. The morphology of the hydrogels affects the properties of the obtained nanocomposites. The microbiological tests have shown that the D-g-PAA-based hydrogels loaded with AgNPs are more active against Staphylococcus aureus than their PAA-based counterparts and can be an efficient alternative to antibiotic-containing coverings and dressings.

Applied Nanoscience, 2021

The multi-component nanosystems based on the branched copolymer dextran-graft-polyacrylamide in a... more The multi-component nanosystems based on the branched copolymer dextran-graft-polyacrylamide in an anionic form (D-g-PAAan) with gold nanoparticles (AuNPs), photosensitizer Chlorine e6 (Ce6), and chemotherapeutic agent Doxorubicin (Dox) were developed for use in complex breast cancer therapy. The synthesized nanosystems were characterized by Quasi Elastic Light Scattering and Transmission Electron Microscopy and tested against the malignant cells MCF-7/Dox resistant to Dox. It is found that the addition of Dox as the fourth component to the three-component nanosystem D-g-PAAan/AuNPs/Ce6 leads to aggregation and, as a result, to decrease in efficiency of tumor treatment. The way to reduce unwanted aggregation in the four-component nanosystem D-g-PAAan/AuNPs/Ce6/Dox is proposed. The new nanosystems are shown to be effective in overcoming Dox resistance and killing cancer cells.

Chemical Engineering of Polymers, 2017

Two series of Dextran-graft-Polyacrylamide copolymers with polysaccharide backbone having differe... more Two series of Dextran-graft-Polyacrylamide copolymers with polysaccharide backbone having different molecular weights (Mw = 20 000 and Mw = 70 000) and long grafted Polyacrylamide chains were synthesized by radical copolymerization using Ceric-ion-induced redox initiation. A certain fraction of ionic sites was introduced into the PAA grafts by alkaline hydrolysis during different time periods (NH2 groups were changed by OH groups) in order to convert D-g-PAA into polyelectrolyte. It was established that D-g-PAA copolymers both in non-ionic and in ionic form can adsorb transition metal ions from aqueous solution. These copolymers have high flocculation efficiency due to their expanded conformation in water solution. The flocculation ability is inversely related to the spacing of the PAA grafts (i.e. the length of backbone between the grafts).

Molecular Crystals and Liquid Crystals, 2007

ABSTRACT makes every effort to ensure the accuracy of all the information (the "Cont... more ABSTRACT makes every effort to ensure the accuracy of all the information (the "Content") contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content.

Journal of Molecular Liquids, 2017

Uncharged and anionic copolymers Dextran-graft-Polyacrylamide (D-g-PAA) and linear PAA of similar... more Uncharged and anionic copolymers Dextran-graft-Polyacrylamide (D-g-PAA) and linear PAA of similar molecular weight were tested as flocculants in model kaolin polydisperse suspensions (C = 3 g/dl) having high content of particles less than 2 μm in size (more than 60%) which are difficult to settle down. The flocculation process was characterized by suspension sedimentation rate and degree of supernatant clarification. Dependence of flocculation on the degree of branched copolymers compactness as well as the degree of hydrolysis of the amide groups in the polymers was investigated. The main regularities of selection of suitable branched flocculants based on D-g-PAA and optimal their concentration for effective flocculation process was obtained. It was shown that D-g-PAA in ionic form with the lower grafting efficiency and long PAA grafts ensured the highest degree of supernatant clarification and the highest rate of the suspension sedimentation.

AIP Conference Proceedings, 2008

ABSTRACT Branched polymers Dextran-graft-Polyacrylamide and Dextran Sulphate-graft-Polyacrylamide... more ABSTRACT Branched polymers Dextran-graft-Polyacrylamide and Dextran Sulphate-graft-Polyacrylamide copolymers with long polysaccharide backbone and various amount and length of PAA-grafts were synthesised by radical polymerization using Ce(IV)/HNO3 redox system. It was established, that these copolymers have expanded conformation in solution and are able to intramolecular structure formation. Grafting efficiency is conditioned by amount of initiator and Dextran (or Dextran Sulphate) conformation in solution. It was shown that increase in content of copolymer Polyacrylamide component in Dextran Sulphate-graft-Polyacrylamide copolymers causes decrease in size of macromolecule due to blocking of polyion charge of main polysaccharide chain by counterions.

Nanoscale Advances

The development of precision cancer medicine relies on novel formulation strategies for targeted ... more The development of precision cancer medicine relies on novel formulation strategies for targeted drug delivery to increase the therapeutic outcome.

Polymer, 2006

Copolymers obtained by grafting polyacrylamide (PAA) onto polydextran (DEX) have been synthesised... more Copolymers obtained by grafting polyacrylamide (PAA) onto polydextran (DEX) have been synthesised by ceric-ion-reduced redox initiation method. These copolymers have been characterized by light scattering, self-exclusion chromatography and viscometry in aqueous solutions. The short range molecular structure has been studied by small-angle X-ray scattering. From these results it is suggested that close to the anchoring point the grafted chains are extended while they take on a random conformation far from this point. A few investigations have been carried out in water/DMF (dimethyl formamide) mixtures. It is observed that the molecular weight depends strongly on the dimethyl formamide fraction. These results are discussed by contemplating the existence of PAA/DMF complexes.

Brazilian Journal of Physics, 2006

Micron-sized spheres of mesoporous styrene-divinylbenzene (Sty-DVB) copolymer were produced by su... more Micron-sized spheres of mesoporous styrene-divinylbenzene (Sty-DVB) copolymer were produced by suspension polymerisation in the presence of inert diluents. Using these mesoporous microspheres as a template, optically stable CdS nanoparticles have been synthesized. To characterize these CdS nanoparticles, Raman spectroscopy and micro-photoluminescence were used. We have observed enhanced emission and lasing action at certain wavelengths that correspond to the whispering gallery (WG) modes of the microspheres. High optical stability and low threshold value make this optical system promising in microlaser applications.

Molecular Crystals and Liquid Crystals

Abstract Hydrogel absorbents were synthesized based on cross-linking of Polyacrylamide grafted on... more Abstract Hydrogel absorbents were synthesized based on cross-linking of Polyacrylamide grafted on Dextran or Dextran sulfate sodium salt. It was found that the swelling capacity of hydrogels depends on cross-linker concentration as well as Dextran component. FT-IR studies of hydrogels were carried out to analyze its structure. Methylene blue dye as model cationic medical drug was applied for the absorption/desorption study. Hybrid hydrogels prove the mechanism of absorption by the formation of charged polyelectrolyte/dye complexes. The kinetic model of pseudo-first order was applied to determine the rate constant k of the reaction between hydrogels and dye in the solution.

Springer Proceedings in Physics, 2021

Chemical Engineering of Polymers, 2017

Molecular Crystals and Liquid Crystals, 2021

Abstract Methylene blue as photosensitizer was used for antimicrobial photoinactivation of Staphy... more Abstract Methylene blue as photosensitizer was used for antimicrobial photoinactivation of Staphylococcus aureus in suspension. The antimicrobial activity of methylene blue was activated by red light of low energy density. Determination of CFU in bacterial suspensions was performed in the Goryaev chamber after staining an aliquot of the suspension with Acridine orange. A reduction of CFU/mL of S. aureus to 60% was achieved. The study of antibacterial efficacy of laser light with wavelengths (λex) of 390, 460 and 660 and different energy density against wild strains of S. aureus was carried out for comparison.

Branched nanostructured copolymers dextran-g-polyacrylamide (D-g-PAA) in uncharged and anionic fo... more Branched nanostructured copolymers dextran-g-polyacrylamide (D-g-PAA) in uncharged and anionic form were synthesized, characterized, and tested for flocculation in comparison with linear PAA. The polymers differed in the conformation of grafted polyacrylamide chains determining the molecular compactness. Kaolin clay dispersion with a high content (more than 60%) of particles less than 2 μm in size, which settle down with difficulty, was used as a model system. It was shown that branched copolymers exhibited high flocculation activity in noncharged and ionic forms. In contrast to linear polymers, not only the size of the macromolecule polymer flocculants but also their molecular nanostructure affected the parameters (sedimentation rate and degree of supernatant clarification) of the flocculation process. The degree of supernatant clarification for branched polymers at optimal flocculant concentrations was higher than for linear PAA. Branched and linear flocculants in anionic form wer...

Springer Proceedings in Physics, 2019

The comparative refractive index analysis for two systems, Au sol synthesized into solution of de... more The comparative refractive index analysis for two systems, Au sol synthesized into solution of dextran-graft-polyacrylamide (D-g-PAA) starlike copolymer and solution of D-g-PAA under laser illumination, has been carried out. It was established that Au nanoparticles (AuNPs) are 1.5–6 nm in size. The size of individual polymer molecule in solution was equal to 50–60 nm. Au/D-g-PAA nanosystem was successfully used as nanocarrier for photodynamic anticancer therapy.

Springer Proceedings in Physics, 2019

Poly-N-isopropylacrylamide (PNIPAAm) is a biocompatible thermosensitive polymer that is promising... more Poly-N-isopropylacrylamide (PNIPAAm) is a biocompatible thermosensitive polymer that is promising for use in nanobiotechnology applications since this polymer has a phase transition temperature (LCST) in the physiological temperature range. LCST can be regulated by changing the hydrophilic-hydrophobic balance of the PNIPAAm-containing macromolecule or by changing its structure. The radical copolymerization method was used for the synthesis of the starlike copolymers with dextran core of various molecular weights and with various amounts of grafted dextran-poly-N-isopropylacrylamide (D-PNIPAAm) chains. It was shown that reducing the distance between PNIPAAm grafts affects the conformational transition characteristics of the polymer.

Applied Nanoscience, 2021

The hydrogels based on cross-linked dextran-graft-polyacrylamide (D-g-PAA) and polyacrylamide (PA... more The hydrogels based on cross-linked dextran-graft-polyacrylamide (D-g-PAA) and polyacrylamide (PAA) with different densities of chemical cross-links were synthesized by radical polymerization. They were used as nanoreactors for the photochemical synthesis of silver nanoparticles (AgNPs). The polymer hydrogels and nanocomposites with loaded AgNPs were characterized by SEM, FTIR- and UV–Vis spectroscopy. Swelling studies demonstrated differences in the internal structure of the cross-linked D-g-PAA and PAA samples. The morphology of the hydrogels affects the properties of the obtained nanocomposites. The microbiological tests have shown that the D-g-PAA-based hydrogels loaded with AgNPs are more active against Staphylococcus aureus than their PAA-based counterparts and can be an efficient alternative to antibiotic-containing coverings and dressings.

Applied Nanoscience, 2021

The multi-component nanosystems based on the branched copolymer dextran-graft-polyacrylamide in a... more The multi-component nanosystems based on the branched copolymer dextran-graft-polyacrylamide in an anionic form (D-g-PAAan) with gold nanoparticles (AuNPs), photosensitizer Chlorine e6 (Ce6), and chemotherapeutic agent Doxorubicin (Dox) were developed for use in complex breast cancer therapy. The synthesized nanosystems were characterized by Quasi Elastic Light Scattering and Transmission Electron Microscopy and tested against the malignant cells MCF-7/Dox resistant to Dox. It is found that the addition of Dox as the fourth component to the three-component nanosystem D-g-PAAan/AuNPs/Ce6 leads to aggregation and, as a result, to decrease in efficiency of tumor treatment. The way to reduce unwanted aggregation in the four-component nanosystem D-g-PAAan/AuNPs/Ce6/Dox is proposed. The new nanosystems are shown to be effective in overcoming Dox resistance and killing cancer cells.