Elmarco Ltd.

Liberec, Czech Republic

Elmarco Ltd.

Liberec, Czech Republic
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Dubsky M.,Academy of Sciences of the Czech Republic | Dubsky M.,Institute for Clinical and Experimental Medicine | Kubinova S.,Academy of Sciences of the Czech Republic | Sirc J.,Czech Institute of Macromolecular Chemical | And 11 more authors.
Journal of Materials Science: Materials in Medicine | Year: 2012

Electrospun gelatin and poly-e-caprolactone (PCL) nanofibers were prepared using needleless technology and their biocompatibility and therapeutic efficacy have been characterized in vitro in cell cultures and in an experimental model of a skin wound. Human dermal fibroblasts, keratinocytes and mesenchymal stem cells seeded on the nanofibers revealed that both nanofibers promoted cell adhesion and proliferation. The effect of nanofibers on wound healing was examined using a full thickness wound model in rats and compared with a standard control treatment with gauze. Significantly faster wound closure was found with gelatin after 5 and 10 days of treatment, but no enhancement with PCL nanofibers was observed. Histological analysis revealed enhanced epithelialisation, increased depth of granulation tissue and increased density of myofibroblasts in the wound area with gelatin nanofibers. The results show that gelatin nanofibers produced by needleless technology accelerate wound healing and may be suitable as a scaffold for cell transfer and skin regeneration. © Springer Science+Business Media, LLC 2012.

Sirc J.,Czech Institute of Macromolecular Chemical | Kubinova S.,Academy of Sciences of the Czech Republic | Hobzova R.,Czech Institute of Macromolecular Chemical | Stranska D.,Elmarco Ltd | And 6 more authors.
International Journal of Nanomedicine | Year: 2012

Polyvinyl alcohol nanofibers incorporating the wide spectrum antibiotic gentamicin were prepared by Nanospider™ needleless technology. A polyvinyl alcohol layer, serving as a drug reservoir, was covered from both sides by polyurethane layers of various thicknesses. The multilayered structure of the nanofibers was observed using scanning electron microscopy, the porosity was characterized by mercury porosimetry, and nitrogen adsorption/desorption measurements were used to determine specific surface areas. The stability of the gentamicin released from the electrospun layers was proved by high-performance liquid chromatography (HPLC) and inhibition of bacterial growth. Drug release was investigated using in vitro experiments with HPLC/MS quantification, while the antimicrobial efficacy was evaluated on Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa. Both experiments proved that the released gentamicin retained its activity and showed that the retention of the drug in the nanofibers was prolonged with the increasing thickness of the covering layers. © 2012 Cárdenas et al, publisher and licensee Dove Medical Press Ltd.

Bacakova M.,Academy of Sciences of the Czech Republic | Lopot F.,Charles University | Hadraba D.,Academy of Sciences of the Czech Republic | Hadraba D.,Charles University | And 5 more authors.
Journal of Biomaterials Applications | Year: 2015

It may be possible to regulate the cell colonization of biodegradable polymer nanofibrous membranes by plasma treatment and by the density of the fibers. To test this hypothesis, nanofibrous membranes of different fiber densities were treated by oxygen plasma with a range of plasma power and exposure times. Scanning electron microscopy and mechanical tests showed significant modification of nanofibers after plasma treatment. The intensity of the fiber modification increased with plasma power and exposure time. The exposure time seemed to have a stronger effect on modifying the fiber. The mechanical behavior of the membranes was influenced by the plasma treatment, the fiber density, and their dry or wet state. Plasma treatment increased the membrane stiffness; however, the membranes became more brittle. Wet membranes displayed significantly lower stiffness than dry membranes. X-ray photoelectron spectroscopy (XPS) analysis showed a slight increase in oxygen-containing groups on the membrane surface after plasma treatment. Plasma treatment enhanced the adhesion and growth of HaCaT keratinocytes on nanofibrous membranes. The cells adhered and grew preferentially on membranes of lower fiber densities, probably due to the larger area of void spaces between the fibers. © The Author(s) 2014.

Macak J.M.,Elmarco Ltd. | Pytel J.,Elmarco Ltd. | Ruiz J.R.,University of Cagliari | Beranek R.,Friedrich - Alexander - University, Erlangen - Nuremberg
Materials Research Society Symposium Proceedings | Year: 2010

Photoelectrochemical properties of photoelectrodes consisting of pressed layers of electrospun TiO2 nanoflbers were investigated by wavelength-resolved photocurrent measurements in LiClO4 (0.1 M) aqueous electrolyte with or without addition of KI as an additional hole scavenger. The photocurrents on nanofiber electrodes were three-times lower as compared to electrodes based on Hombikat nanocrystalline particles. The calcination of electrodes was necessary to observe enhanced efficiencies in the presence of iodide. The most striking difference between nanofiber and particulate electrodes was found in the effect of calcination on the efficiency of water photooxidation. © 2010 Materials Research Society.

Sirc J.,Czech Institute of Macromolecular Chemical | Hobzova R.,Czech Institute of Macromolecular Chemical | Kostina N.,Czech Institute of Macromolecular Chemical | Munzarova M.,Elmarco Ltd. | And 5 more authors.
Journal of Nanomaterials | Year: 2012

Biomedical applications such as wound dressing for skin regeneration, stem cell transplantation, or drug delivery require special demands on the three-dimensional porous scaffolds. Besides the biocompatibility and mechanical properties, the morphology is the most important attribute of the scaffold. Specific surface area, volume, and size of the pores have considerable effect on cell adhesion, growth, and proliferation. In the case of incorporated biologically active substances, their release is also influenced by the internal structure of nanofibers. Although many scientific papers are focused on the preparation of nanofibers and evaluation of biological tests, the morphological characterization was described just briefly as service methods. The aim of this paper is to summarize the methods applicable for morphological characterization of nanofibers and supplement it by the results of our research. Needleless electrospinning technique was used to prepare nanofibers from polylactide, poly(ε-caprolactone), gelatin, and polyamide. Scanning electron microscopy was used to evaluate the fiber diameters and to reveal eventual artifacts in the nanofibrous structure. Nitrogen adsorption/desorption measurements were employed to measure the specific surface areas. Mercury porosimetry was used to determine total porosities and compare pore size distributions of the prepared samples. © 2012 Jakub Širc et al.

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