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More than half of the hospital-associated infections worldwide are related to the adhesion of bacteria cells to biomedical devices and implants. To prevent these infections, it is crucial to modify biomaterial surfaces to develop the antibacterial property. In this study, chitosan (CS) and chondroitin sulfate (ChS) were chosen as antibacterial coating materials on polylactic acid (PLA) surfaces. Plasma-treated PLA surfaces were coated with CS either direct coating method or the carbodiimide coupling method. As a next step for the combined saccharide coating, CS grafted samples were immersed in ChS solution, which resulted in the polyelectrolyte complex (PEC) formation. Also in this experiment, to test the drug loading and releasing efficiency of the thin film coatings, CS grafted samples were immersed into lomefloxacin-containing ChS solution. The successful modifications were confirmed by elemental composition analysis (XPS), surface topography images (SEM), and hydrophilicity change (contact angle measurements). The carbodiimide coupling resulted in higher CS grafting on the PLA surface. The coatings with the PEC formation between CS-ChS showed improved activity against the bacteria strains than the separate coatings. Moreover, these interactions increased the lomefloxacin amount adhered to the film coatings and extended the drug release profile. Finally, the zone of inhibition test confirmed that the CS-ChS coating showed a contact killing mechanism while drug-loaded films have a dual killing mechanism, which includes contact, and release killing.

This paper reposts on nanofibers of polymers doped with ferrous sulphate (FeSO4) possibly in combination with quaternary ammonium salt (QAS) prepared by electrospinning. Three types of polymers (polyvinylidene fluoride/PVDF, polylactic acid/PLA and polyurethane/PU) with good electrospinning processability and good mechanical properties of nanofibers were chosen. The prepared nanofibrous membranes were characterised in terms of morphology of the fibres assessed by SEM, and the pore sizes were determined by porometry. The leaching test showed a firm anchoring of the additive in the nanofiber structure. Antimicrobial activity was monitored after 0 h, 4 h and 24 h using Staphylococcus aureus (CCM 4516) and Klebsiella pneumoniae (CCM 4415) strains. Furthermore, aerosol filtration efficycy was dermined and also quality factor of filtration. The membrane prepared from PU doped with FeSO4 showed the best antibacterial efficiency. The porosity and morphology of the nanofibrous membrane effectively contributed to the trapping of microorganisms. This system was also evaluated as the most suitable for the electrospinning process from the effectivity point of view. Spinning ang dopping process of preparation is easily applicatbole to the the industrial conditions of production which is very importatnt aspect of this submitted scientifique work. © 2021 NANOCON Conference Proceedings - International Conference on Nanomaterials. All rights reserved.

The development of antibacterial materials has great importance in avoiding bacterial contamination and the risk of infection for implantable biomaterials. An antibacterial thin film coating on the surface via chemical bonding is a promising technique to keep native bulk material properties unchanged. However, most of the polymeric materials are chemically inert and highly hydrophobic, which makes chemical agent coating challenging Herein, immobilization of chlorhexidine, a broad-spectrum bactericidal cationic compound, onto the polylactic acid surface was performed in a multistep physicochemical method. Direct current plasma was used for surface functionalization, followed by carbodiimide chemistry to link the coupling reagents of N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDAC) and N-Hydroxysuccinimide (NHs) to create a free bonding site to anchor the chlorhexidine. Surface characterizations were performed by water contact angle test, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). The antibacterial activity was tested using Staphylococcus aureus and Escherichia coli. Finally, in vitro cytocompatibility of the samples was studied using primary mouse embryonic fibroblast cells. It was found that all samples were cytocompatible and the best antibacterial performance observed was the Chlorhexidine immobilized sample after NHs activation. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Many polymer materials have found a wide variety of applications in biomedical indus-tries due to their excellent mechanical properties. However, the infections associated with the bio-film formation represent serious problems resulting from the initial bacterial attachment on the polymeric surface. The development of novel slippery liquid-infused porous surfaces (SLIPSs) repre-sents promising method for the biofilm formation prevention. These surfaces are characterized by specific microstructural roughness able to hold lubricants inside. The lubricants create a slippery layer for the repellence of various liquids, such as water and blood. In this study, effective antimi-crobial modifications of polyethylene (PE) and polyurethane (PU), as commonly used medical pol-ymers, were investigated. For this purpose, low-temperature plasma treatment was used initially for activation of the polymeric surface, thereby enhancing surface and adhesion properties. Subse-quently, preparation of porous microstructures was achieved by electrospinning technique using polydimethylsiloxane (PDMS) in combination with polyamide (PA). Finally, natural black seed oil (BSO) infiltrated the produced fiber mats acting as a lubricating layer. The optimized fiber mats’ production was achieved using PDMS/PA mixture at ratio 1:1:20 (g/g/mL) using isopropyl alcohol as solvent. The surface properties of produced slippery surfaces were analyzed by various microscopic and optics techniques to obtain information about wettability, sliding behavior and surface morphology/topography. The modified PE and PU substrates demonstrated slippery behavior of an impinged water droplet at a small tilting angle. Moreover, the antimicrobial effects of the produced SLIPs using black seed oil were proven against Gram-positive Staphylococcus aureus (S. au-reus) and Gram-negative Escherichia coli (E. coli). © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Polylactic acid (PLA) is one of the most produced polymeric materials, due to its exceptional chemical and mechanical properties. Some of them, such as biodegradability and biocompatibility, make them attractive for biomedical applications. Conversely, the major drawback of PLA in the biomedical field is their vulnerability to bacterial contamination. This study focuses on the immobilization of saccharides onto the PLA surface by a multistep approach, with the aim of providing antibacterial features and evaluting the synergistic effect of these saccharides. In this approach, after poly (acrylic acid) (PAA) brushes attached non-covalently to the PLA surface via plasma post-irradiation grafting technique, immobilization of glucosamine (GlcN) and chondroitin sulfate (ChS) to the PAA brushes was carried out. To understand the changes in surface properties, such as chemical composition, surface topography and hydrophilicity, the untreated and treated PLA films were analyzed using various characterization techniques (contact angle, scanning electron microscopy, X-ray photoelectron spectroscopy). In vitro cytotoxicity assays were investigated by the methyl tetrazolium test. The antibacterial activity of the PLA samples was tested against Escherichia coli and Staphylococcus aureus bacteria strains. Plasma-treated films immobilized with ChS and GlcN, separately and in combination, demonstrated bactericidal effect against the both bacteria strains and also the results revealed that the combination has no synergistic effect on antibacterial action. © 2019 by the authors.

The use of polymers in all aspects of daily life is increasing considerably, so there is high demand for polymers with specific properties. Polymers with antibacterial properties are highly needed in the food and medical industries. Low-density polyethylene (LDPE) is widely used in various industries, especially in food packaging, because it has suitable mechanical and safety properties. Nevertheless, the hydrophobicity of its surface makes it vulnerable to microbial attack and culturing. To enhance antimicrobial activity, a progressive surface modification of LDPE using the antimicrobial agent grafting process was applied. LDPE was first exposed to nonthermal radio-frequency (RF) plasma treatment to activate its surface. This led to the creation of reactive species on the LDPE surface, resulting in the ability to graft antibacterial agents, such as ascorbic acid (ASA), commonly known as vitamin C. ASA is a well-known antioxidant that is used as a food preservative, is essential to biological systems, and is found to be reactive against a number of microorganisms and bacteria. The antimicrobial effect of grafted LDPE with ASA was tested against two strong kinds of bacteria, namely, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), with positive results. Surface analyses were performed thoroughly using contact angle measurements and peel tests to measure the wettability or surface free energy and adhesion properties after each modification step. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to analyze the surface morphology or topography changes of LDPE caused by plasma treatment and ASA grafting. Surface chemistry was studied by measuring the functional groups and elements introduced to the surface after plasma treatment and ASA grafting, using Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). These results showed wettability, adhesion, and roughness changes in the LDPE surface

Bacterial contamination is one of the biggest drawbacks of implanted biomaterials, which may cause nosocomial infection. Avoiding bacterial adhesion onto the biomaterial surface by preparing active antibacterial biomaterials is an accurate solution. In this study, three of the fluoroquinolones: sparfloxacin, enrofloxacin, and lomefloxacin were selected due to their broad bactericidal effect and immobilized onto low-density polyethylene surface at two different pH values (pH 3 and pH 6), after tailoring the surface by plasma treatment followed by grafting of polymer brush of N-allylmethylamine. Surface wettability test and morphological investigations were carried out by water contact angle measurement and scanning electron microscopy analysis, respectively. Chemical characterizations were carried out by Fourier transform infrared spectra and X-ray photoelectron spectroscopy. Antibacterial activity was checked against Staphylococcus aureus and Escherichia coli strains and results revealed that prepared surfaces were more effective against E. coli than S. aureus especially those prepared at pH 6. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46174. © 2017 Wiley Periodicals, Inc.

Hydrogelová kompozice obsahuje hydrogelovou matrici tvořenou síťovanou polymerní strukturou na bázi alespoň jednoho vodorozpustného polymeru ze skupiny zahrnující kopolymery kyseliny akrylové, kopolymery kyseliny methakrylové a deriváty celulózy a v koncentraci 0,001 až 10 % hmot., vztaženo na hmotnost suché hydrogelové matrice, biologicky aktivní aditivum tvořené alespoň jednou biologicky aktivní látkou izolovanou z mléka nebo jeho derivátů, jako je látka ze skupiny glykoproteinů, imunoproteinů, imunoglobulinů a/nebo polypeptidů., Hydrogel composition with the biologically active substances. The hydrogel composition contains the hydrogel matrix, that is formed by cross-linked polymer structure based on at least one water-soluble polymer from the group of acrylic acid copolymers, copolymers of methacrylic acid and cellulose derivatives, in concentrations from 0.001 % to 10 % weight, related to the weight of the dry hydrogel matrix, Biologically active additive comprising at least one biologically active substance isolated from milk or its derivatives, such as the substance from the group glycoproteins, immunoproteins, immunoglobulins and/or polypeptides.

Technické řešení se týká dentálního polymerního gelu s antibakteriálními a hojivými účinky, určeného pro místní léčbu, pro podpůrné, primární i sekundární ošetření zánětů a ran v dutině ústní jak u lidských pacientů, tak i u zvířat., Technical solution relates to a dental polymer gel with antibacterial and healing effects, used for local treatment, for support, both primary and secondary treatment of inflammation and healing in the oral cavity as in human patients, and in animals.

Hydrogelová kompozice obsahuje hydrogelovou matrici, která je tvořena síťovanou polymerní strukturou na bázi vodorozpustných polymerů a v koncentraci 0,001 až 10 hmot. %, vztaženo na hmotnost suché hydrogelové matrice, a biologicky aktivní aditivum tvořené alespoň jednou biologicky aktivní látkou izolovanou z mléka nebo jeho derivátů. Hydrogelovou matricí je s výhodou síťovaná polymerní struktura na bázi alespoň jednoho polymeru ze skupiny zahrnující kopolymery kyseliny akrylové, kopolymery kyseliny methakrylové, deriváty celulózy a vinylové polymery. Biologicky aktivní látkou izolovanou z mléka nebo jeho derivátů je především látka ze skupiny glykoproteinů, imunoglobulinů a/nebo polypeptidů.

Hydrogelová kompozice obsahuje hydrogelovou matrici, která je tvořena síťovanou polymerní strukturou na bázi vodorozpustných polymerů a v koncentraci 0,001 až 10 hmot. %, vztaženo na hmotnost suché hydrogelové matrice, a biologicky aktivní aditivum tvořené alespoň jednou biologicky aktivní látkou izolovanou z mléka nebo jeho derivátů. Hydrogelovou matricí je s výhodou síťovaná polymerní struktura na bázi alespoň jednoho polymeru ze skupiny zahrnující kopolymery kyseliny akrylové, kopolymery kyseliny methakrylové, deriváty celulózy a vinylové polymery. Biologicky aktivní látkou izolovanou z mléka nebo jeho derivátů je především látka ze skupiny glykoproteinů, imunoglobulinů a/nebo polypeptidů.