Zbigniew Draczyński

PLA/PHA-Biodegradable Blends for Pneumothermic Fabrication of Nonwovens

Abstract This study presents the results of research concerning fabrication of nonwovens from biodegradable polymer blends using the melt-blown method. The experiments performed within the framework of the research confirmed the possibility of obtaining polymer composites based on polylactide (PLA) with poly(hydroxyalkanoates) (PHA) and another aliphatic-aromatic copolyester. The obtained products were subjected to the analyses of chemical structure using the Fourier Transform Infrared Spectroscopy(FTIR) Attenuated Total Reflectance(ATR) method. The physical and mechanical properties of the fabricated nonwoven layers were also tested, which confirmed a wide spectrum of their applicability, depending on the polymer composition used in production.

New generation butyric-acetate copolymer of chitin (BOC) fibres with ceramic HAp and TCP nanoadditives for the manufacture of fibrous composite materials

An investigation was made of the effect of basic spinning process parameters on the structure and properties of butyric-acetate copolymer of chitin (BOC) fibres. It was found that, considering the resulting tenacity of 20.3 cN/tex simultaneously with high water sorption and retention properties, it is favourable for the BOC fibre spinning process to be carried out with 1 % HAp or TCP nanoadditive. Furthermore, when 3 % of the HAp or TCP nanoadditive is incorporated into the BOC fibre material, no significant changes in the crystal structure occur compared with fibres without the nanoadditives, formed in similar conditions. Analysis of the porous structure and the properties of the surface of BOC fibres with HAp or TCP nanoadditive shows that the parameters are favourable for their medical application.

Search for Fibrous Aggregates Potentially Useful in Regenerative Medicine Formed under Physiological Conditions by Self-Assembling Short Peptides Containing Two Identical Aromatic Amino Acid Residues

This study investigates the propensity of short peptides to self-organize and the influence of aggregates on cell cultures. The dipeptides were derived from both enantiomers of identical aromatic amino acids and tripeptides were prepared from two identical aromatic amino acids with one cysteine or methionine residue in the C-terminal, N-terminal, or central position. The formation or absence of fibrous structures under physiological conditions was established using Congo Red and Thioflavine T assays as well as by microscopic examination using normal and polarized light. The in vitro stability of the aggregates in buffered saline solution was assessed over 30 days. Materials with potential for use in regenerative medicine were selected based on the cytotoxicity of the peptides to the endothelial cell line EA.hy 926 and the wettability of the surfaces of the films, as well as using scanning electron microscopy. The criteria were fulfilled by H-dPhedPhe-OH, H-dCysdPhedPhe-OH, H-CysTyrTyr-OH, H-dPhedPhedCys-OH, H-TyrTyrMet-OH, and H–TyrMetTyr–OH. Our preliminary results suggest that the morphology and cell viability of L919 fibroblast cells do not depend on the stereochemistry of the self-organizing peptides.

Analysis of structure and properties of antibacterial vascular patch used in abdominal aorta aneurysm surgeries

Background: Biocompatible materials are used for treatment of blood circulatory system diseases, especially abdominal aortic aneurysms. The most popular and often used are knitted and polymer vascular patches. The aim of this study was to optimize the manufacturing process of implantable materials, ensuring antibacterial activity useful for treating abdominal aorta aneurysms. Methods: The vascular patch was manufactured from Trevira® yarn. The parameters of the intermediate product and vascular patch were tested according to standard procedures. Results: The vascular patch, manufactured from microsilver-containing yarn, with crimps on the surface of the patch, has been found useful for treatment of abdominal aorta aneurysms. Introducing crimps on the surface of the patch resulted in reduction of water permeability and enabled cutting of the graft at various angles without fraying at the cut ends of the biomaterial. The final vascular patch was marked by a gradual release of silver within 48 hours. Conclusions: On the basis of the performed test, it has been demonstrated that an implantable material for the treatment of abdominal aorta aneurysms was obtained, and that it can be considered as an alternative for currently used vascular patches. The final vascular patch was marked by a gradual release of silver during the first period of incubation. The antibacterial properties of the final product were confirmed by observation of a significant reduction in the number of Staphylococcus aureus and Klebsiella pneumoniae bacterial colonies.

The Analysis of Structure and Physicochemical Properties of Yarns Used for Manufacturing Hernia Meshes

Abstract The article presents a comparative analysis of the yarns used for manufacturing hernia meshes. For the analysis, two different linear masses, 46 dtex and 72 dtex, of transparent and dyed yarns were used; the dye used in the yarns was adequate for their intended use. The DSC tests showed the influence of thermal treatment on the change of thermal properties of the yarns. At the same time, it was proved that the aforementioned treatment had a bearing on the changes of crystallinity degree. All types of yarns were also subjected to physicochemical tests required for all the materials used for the production of hernia meshes.