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Silver-containing film materials are formed by vacuum sputtering of silver nanoparticles on the surface of polyelectrolyte complexes based on chitosan and sodium salt of carboxymethylcellulose (pectin). The obtained samples were characterized by the methods of wide-angle X-ray scattering and transmission electron microscopy, and their antimicrobial, antiviral and cytotoxic properties were also investigated. The presence of metallic silver on the surface of polyelectrolyte complexes was confirmed by the method of wide-angle X-ray diffraction. It was established that upon sputtering of silver, a ~200 nm thick layer is formed within 5 minutes. It was shown that Na-CMC--Ag--chitosan and pectin--Ag--chitosan samples, formed by silver sputtering, exhibit antimicrobial activity against test cultures of S. aureus, E. coli, P. aeruginosa, and C. albicans. Antiviral activity of samples against influenza A virus and herpes simplex virus type 1 was also established. The obtained samples were not cytotoxic, did not inhibit the viability of MDCK and BHK cell cultures. [ABSTRACT FROM AUTHOR]

Infectious diseases caused by viruses and microorganisms continue to be one of the biggest health problems worldwide, despite the rapid progress in the creation of drugs and the development of pharmaceutical technologies. Th e risk of complications and the spread of infections in society remains high. Scientifi c research and the fi ght against viral infections, in particular with a large group of respiratory diseases caused by viruses, such as infl uenza viruses, parainfl uenza viruses, respiratory sensitivities, adenoviruses, rhinoviruses, coronaviruses, etc., occupy an important place in modern medicine. Due to the nature, characteristics and biological and physical properties of viruses, the issues of combating them are very acute. Microorganisms resistant to many antimicrobial agents are also developing (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, etc.). Th erefore, today there is an urgent need for new materials with a higher antiviral and bactericidal eff ect, less toxicity for humans and the environment (ecology, medicine and food industry). Silver-containing biomaterials in various forms (powders, fi lms, solutions, products formed by 3D printing technology) with eff ective antimicrobial and antiviral eff ects have been developed. Th e materials are made on the basis of polyelectrolyte complexes of polysaccharides (pectin – chitosan, pectin – cationic starch, carboxymethylcellulose – cationic β-cyclodextrin, anionic starch – cationic starch) and polylactide biopolymer. Silver nanoparticles in the composition of composites were formed in environmentally friendly ways: by reduction silver ions with extracts of natural substances (green tea, mint, propolis, pectin), by methods of thermochemical reduction or cathodic sputtering of silver nanoparticles from silver foil onto the surface of the fi lm. Th e structure, morphology, obtained materials and their antimicrobial, antiviral and cytotoxic properties were studied. Th e relationship between the structure and morphology and the protective properties of the obtained materials was studied. [ABSTRACT FROM AUTHOR]

Using FT-IR-spectroscopy, X-ray diffraction and thermomechanical analysis structure and thermomechanical properties of two nonstoichiometry and one stoichiometry polyelectrolyte complexes (PEC) based on opposite charged polyelectrolytes - strong cationic polyelectrolyte (chitosan chloride) and weak anionic polyelectrolyte (polyacrylic aсid) and triple polyelectrolyte-metal complexes (TPMC) based on stoichometry polyelectrolyte complexes and cations Cu(II) were investigated. It was shown, that chitosan chloride has amorphous-cristallinity structure, which is significantly different from the structure of neat chitosan, and polyacrylic acid posses amorphous structure. Meantime, all PEC samples have amorphous structure, differing from the structure of weak anionic polyelectrolyte, at the same time amorphous structure of nonstoichiometric PECs insignificantly different from that of stoichiometric polyelectrolyte complexes. Additionally, amorphous structure of TPMC has another structure, compared to all PEC. According to thermomechanical analysis, all PECs have one temperature transition from glassy to highly elastic state (from 77 to 84 °C). The deformation value of the samples of nonstoichiometric PEC is similar and somewhat less than the deformation of the stoichiometric PEC. The TPMC sample has two glass transitions (81 and 226 °C), and his high-temperature transition characterizes the segmental mobility of fragments of macromolecules of one stoichiometric PEC, the polar groups of which form chelate circles with Cu (II) cations. Deformation parameter of the TPMC is higher in comparison with the stoichiometric polyelectrolyte complexes. [ABSTRACT FROM AUTHOR]

Using methods of x-ray diffraction (diffractometre DRON-4-07, CuK -radiation, x-ray - optical sheme of Debai-Sherrer's) and thermomechanical analysis (thermomechanical plant UIP-70, methode penetration, burden 0,5 MPa) were investigated of nanocomposites of type polymer-metal based on stehiometric polyelectrolyte complexe that was obtained from 5% water losung of contrary charge of polyelectrolytes - chitosan and carboxylised ß-cyclodextrin. By modificate of polyelectrolyte complex by salts of CuSO4 and AgNO3 was acquired triple polyelectrolyte-metal complexe. During chemical reduced with the help salt NaBH4 of metal cations of Cu2+ and Ag+ in volyme of triple polyelectrolyte-metal complexe (molar ratio [BH4-] : [Ag+] = 1,0 and [BH4-] : [Cu2+] = 2,0) was acquired of polymer - metalic nanocomposites. Identification of carboxylised ß-cyclodextrin was using FTIR-spectroscopy. Shown that in contrast to initial ß-cyclodextrin the carboxylised ß-cyclodextrin have smaller index crystallinity. By using x-ray diffraction esteblished that polymer - metalic nanocomposites have nanoparticles as crystals of Cu0 (with insignificant amount crystals of Cu2O) and Ag0. Shown that nanocomposites have more high temperature transition from glassy to highelastic states in comparison polyelectrolyte complexe. Discovered that nanocomposite with nanoparticles Cu0/Cu2O by temperatures 190-200 °C heve transition of precrystallization of polymer matrix with further her slow softening, whereas polyelectrolyte complex and nanocoposite with nanoparticles Ag0 heve temperature transition of melting of crystalline phase. 'Ihis polymer - metalic nanocomposites have antibacteriales properties. [ABSTRACT FROM AUTHOR]

Metal-polymer nanocomposites possess unique characteristics and a wide range of applications (for the design of catalytic systems as well as in optoelectronics and nanophotonics). When the polymer matrices are filled with silver and copper nanoparticles, they acquire new valuable properties and can be used as effective antibacterial and antiviral drugs in medicine, pharmacology, and biochemistry. Such materials require a fundamental study of the structure, morphology and antimicrobial properties. The aim of this work is to study the features of the structural organization and antimicrobial activity (in relation to S. aureus and E. coli strains) of polymer films based on polyelectrolyte complexes and copper nanoparticles obtained by chemical and thermochemical reduction of copper ions in polyelectrolyte-metal complexes. The features of structural organization of copper-containing nanocomposites were studied by wide-angle X-ray diffraction on a DRON-4-07 diffractometer, the Xray optical scheme of which was performed to “pass” primary beam radiation through samples. X-ray studies were carried out at T = 20 ± 2 °C in CuKá-radiation, monochromated with a Ni-filter. The antimicrobial activity was studied using reference strains of opportunistic bacteria Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 35218 as model of Gram-positive and Gram-negative bacteria by agar diffusion method on a solid Luria-Bertani nutrient medium. According to the results of the research, it was found out that the optimal conditions for the reductions of copper ions, namely, the duration of the chemical reduction process and its temperature are 2 hours and 170 °C, respectively as well as it was revealed that the obtained materials have high antimicrobial activity on the microorganisms tested (S. aureus and E. coli). In general, it is shown that antimicrobial activity against the test microorganisms are better for the nanocomposites obtained by the thermochemical reduction rather than chemical one. [ABSTRACT FROM AUTHOR]

At present ample quantity publicated of papers on forming and physicochemical propetties of polyelectrolyte complexes free occurence on account of their considerable practical aplication. This polymer systems, as is well known, based on opposite charged polyelectrolytes. However structural organisation of polyelectrolyte complexes practically non vere investigated. At present ample quantity publicated of papers on forming and physicochemical propetties of polyelectrolyte complexes free occurence on account of their considerable practical aplication. This polymer systems, as is well known, based on opposite charged polyelectrolytes. However structural organisation of polyelectrolyte complexes practically non vere investigated. In this connexion, on this work structural organisation two type of polyelectrolyte complexes based on Na-salt of carboxymethyl celllulose and polyethyleneimine or hydrohlouride polyethyleneimine was investigated. Using weide- and small x-ray scattering two type polyelectrolyte complexes based on carboxymethylcellulose and cationic polyelectrolytes with differently ionic force was investigated. It was esteblished that sample polyelectrolyte complexes based weak ionic force cationic polyelectrolyte have amorphous structure whereas based on big ionic force cationic polyelectrolyte have amorphouse-crystalline structure. Was shown that all polyelectrolyte complexes have structure heterogeneity nanoscale type with distribution their region of heterogeneity chaotically on space. The polyelectrolyte complexes with big ionic force of cationic polyelectrolyte have area of heterogeneity bigger in comparison with similar polymer systems based on cationic polyelectrolyte with small ionic force. [ABSTRACT FROM AUTHOR]

Structural organization and antimicrobial properties of nanocomposites based on pectin, polyethyleneimine and Ag nanoparticles, which formed by the chemical and thermochemical reduction methods from polyelectrolyte-metal complexes pectin-Ag+-polyethyleneimine have been investigated. Such type of nanocomposites with Ag nanoparticles incorporated into polymer matrix is obtained due to the chemical reduction of Ag+ ions by NaBH4 in the polyelectrolyte complex. The appearance of the silver metallic phase is observed in full extent while BH4 -: Ag+ molar ratio is equal to 2.0. It is defined that thermochemical reduction of Ag+ ions in polyelectrolyte-metal complexes bulk (while films are heated to the temperature around 100 °С and more) also results in formation of silver-containing nanocomposites. The antimicrobial investigation of the elaborated nanocomposites has been revealed. They possess a high antimicrobial activity against S. aureus and E. coli strains. [ABSTRACT FROM AUTHOR]

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The polyelectrolyte complexes (PEC) from oppositely charged polyelectrolytes – sodium salt of carboxymethyl cellulose and polyethyleneimine hydrochloride at various molar ratios were obtained. The structural organization and thermomechanical properties of the prepared PEC were investigated by means of wide-angle X-ray scattering and thermomechanical analysis. A positive deviation of the experimental values of the glass transition temperature from the calculated ones, according to an additive principle, was revealed for the investigated PEC, which is a proof of the PEC formation. It is shown that the concentration dependence of the attains the maximum value for the stoichiometric composition of the PEC. The structure and thermomechanical behavior of the obtained polyelectrolyte complexes of different compositions vary from those of the initial polyelectrolytes. This effect was explained by the formation of interpolymeric ionic groups and cooperative electrostatic interaction between the anionic and cationic polyelectrolyte. [ABSTRACT FROM AUTHOR]

Using the methods of Infra-Red Fourier spectroscopy, complex of structure investigations and thermomechanical methods, the structure and thermomechanical properties of polyelectrolyte complexes (PEC) with various relation of functional groups (pectin and polyethyleneimine (PEI)) [- COOH]:[-NH2] = 1:3, 1:1, 3:1 have been investigated. Wide-angle X-ray scattering investigation has defined that the average Bragg spacing between macromolecules chains of anionic and cationic electrolytes in the volume of stochiometric-composition PEC (1:1) and pectin-enriched composition PEC (3:1) is equal to 4,3 A, andfor PEC enriched with PEI (1:3) it is equal to 4,4 A. The same method revealed that stochiometric-composition PEC has homogeneous structure - on contrary to non- stochiometric-composition PEC that is featured with micro-heterogeneous structure with effective distance lp in the heterogeneous micro-regions equal to 12 and 38 nm. It is shown that all investigated polymeric systems are typical dielectrics. [ABSTRACT FROM AUTHOR]

The effect of a constant magnetic field on the structure and properties of ternary polyelectrolyte-metal complexes (TPMC) obtained from a stoichiometric polyelectrolyte complex (PEC) based on pectin and polyethyleneimine with Cu2+ ions and nanocomposites formed from these ternary system have been studied by a number of structural techniques and thermomechanical analysis. It is revealed that as a result of chemical reduction a copper ions in the volume of TPMC under the influence of a constant magnetic field occurs with the formation of nanocomposites based on PEC and nanoparticles which consist of only metallic copper phase, whereas in the initial state (without exposure to a magnetic field) is formed nanocomposite PEC-Cu/Cu20. By means of thermomechanical method it is found that under the influence of a constant magnetic field a glass transition temperature Tg increases for PEC-Cu and decreases for PEC and TPMC [ABSTRACT FROM AUTHOR]

Using wide-angle X-rays scattering method, differential scanning calorimetry and methods of thermomechanical analysis some structural and thermal properties of PE-80 and PE-100 polyethylene samples and their hot tool butt welds have been investigated. It was defined that the welded joint of two dissimilar types of polyethylene the structure of which is characterized by recrystallization of the crystalline phase. It is shown that the strength and thermal stability of the welded joint material are higher comparing to these properties of the initial materials; this can be explained texturing of polyethylene microstructure in the welded joint. [ABSTRACT FROM AUTHOR]