Ciprofloxacin, CFL is a drug that belongs to the second generation of fluoroquinolone antibiotics with a wide range of effects on Gram-positive and Gram-negative bacteria. The aim of this work was to investigate the interaction of CFL as ligand with divalent biological cations (Mn2+, Ni2+ and Co2+) in approximate physiological conditions. Synthesized complexes were characterized using FTIR and stereo-microscopy. Antimicrobial screening was performed on bacterial strains of Escherichia coli, Salmonella Enteritidis, Enterococcus faecalis and Staphylococcus aureus. The results of FTIR spectroscopy showed that the M(II) complexes with CFL were formed through the oxygen donors of the carboxyl and carbonyl group of the ligand. Stereo-microscopic characterization revealed the difference in color and size of crystals of the ligand and metal complexes. Antimicrobial screening has shown that CFL and complexes have almost similar antimicrobial activity against investigated bacterial strains.
Polymers based on polystyrene are widely used as thermoplastic materials due to the diversity in application, easy processability and a relatively low price. About 45% of the produced polystyrene is produced as compact and foamed products. Cellular foam polystyrene could be produced as expanded polystyrene (EPS) and extruded polystyrene (XPS) and is mainly used as insulation material. Therefore, physical and chemical properties of expanded and extruded polystyrene is of particular importance for thermal conductivity of the material. In this study, four types of expanded polystyrene were tested. Coefficient of thermal conductivity and the resistance of heat transfer were measured and compared to as well as mecahnical properties of the materials. It was confirmed that the density and thickness of the polystyrene influence the resistance of heat transfer.
The aim of this study was to determine the total phenolic content, evaluate antioxidant propertie and antimicrobial potential, and identify phenolic compounds in alcoholic and aqueous extracts of the wild cherry (Prunus avium L.) stems collected in Bosnia and Herzegovina. Alcoholic extracts had higher contents of phenolic and flavonoid components, as well as the antioxidant and ferric reducing antioxidant capacity in comparison to aqueous extracts. All extracts were characterized by HPLC analysis. Furthermore, for the first time, the antimicrobial properties of wild cherry stem extracts were evaluated. Quercetin and (+)-catechin were the main compounds identified in the alcoholic extract, followed by chlorogenic acid and rutin. Quercetin was also the major component detected in aqueous extracts. Besides, alcoholic extract showed better antibacterial properties against Staphylococcus aureus as a representative gram-positive bacteria than infusion, whereas none of the samples showed antibacterial activity against Escherichia coli and fungus Candida albicans.
Synthetic materials in contact with protein containing solution adsorb a considerable amount of proteins. The adsorption behaviour of zinc-free porcine insulin on the hydrophobic poly(vinylidene fluoride) (PVDF) surfaces before and after chemical vapour deposition (CVD) modification was directly analysed by matrix-assisted laser desorption ionisation-time-of-flight-mass spectroscopy in surface mode (surfaceMALDI-TOF-MS). The MALDI mass spectra of Zn-free porcine insulin dissolved in carbonate buffer pH 8.3 after adsorption onto non-modified and modified PVDF-CVD surfaces contain peaks assigned to monomer ion peak as well as peaks that are results of degradation of Zn-free porcine insulin. The degradation is caused by structural changes taking place during adsorption of insulin onto hydrophobic surfaces and by subsequent laser induced desorption and ionisation process. Surface spectra of Zn-free porcine insulin dissolved in deionised water show only monomer ion peaks of porcine insulin without degradation product detected. Structure stability of Zn-free porcine insulin upon adsorption is influenced by hydrophobic interaction between insulin and the surface.
THE CONTENT OF THE BOOK: The book has 290 pages, and the content is divided into 10 chapters. In the introductory chapters written something about the origin of cocoa beans, its basic characteristics, and the impact on human health. In subsequent following chapters describes the technological process of production of chocolate harvesting, fermentation and drying of cocoa beans, through its preparations in terms in the sense of burning and shredding, the production of cocoa powder and chocolate mass from it, and chocolate and chocolate products. In the book are described rheological properties as a very important factor in the quality of chocolate products, and finally an overview of some types of chocolate, as well as the basic quality properties of chocolate. The book has a large number of pictures, diagrams and tables which are complemented content of book. The book will be published on the website and will be accessible to anyone who is interested in its subject matter.
Contact lenses suffer from two limitations: low oxygen permeability and deposition of protein and lipids. In order to prevent bioadhesion, surface must be completely inert to all biological reactions. To achieve this, surface properties must be tailored. Also, to improve comfort, surface must be highly wettable and lubricous. In this paper the surface of silicone contact lenses was modified by plasma induced copolymerization of acrylic acid. A wettable surface was generated and in addition carboxyl groups that were created on the surface provided an ideal reactive platform for subsequent grafting of polyethylene glycol. Each surface modification step was analysed by XPS and contact angle measurements. Lysozyme adsorption on modified silicone contact lenses was analysed by surface-MALDI-ToF-MS and XPS. After incubation with lysozyme, surface-MALDI-TOF-MS and XPS analysis showed a reduction of adsorbed lysozyme on hydrogel modified contact lenses. Surface modification of silicone with PEG is a method for reduction of protein adsorption on contact lenses.
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