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Biodegradable polymers (biopolymers) represent materials of new generation with application in different areas of human activity. Their production has recently reached a commercial level. They can be divided according to the origin (natural and synthetic), according to the chemical composition, methods of obtaining, application etc. The use of biopolymers in medicine depends on their biocompatibility, mechanical resistance, and sorptive characteristics. Today, they are the most commonly used as implants in vascular and orthopedic surgery, for the production of materials such as catheters, products for gynaecology and haemodialysis, tooth reconstruction, etc. In pharmacy, they are used as a medicine matrix-carrier to allow controlled release of drug within the body. Within this review paper, the properties and methods of production of certain biopolymers such as polyglycolic acid (PGA), polylactide acid (PLA), poly-ε-coprolactone (PCL) and polybutylene succinate (PBS) will be described in detail, as well as their application in medicine and pharmacy.

Cherry (Prunus cerasus var. Oblačinska) is one of the most common varieties in Bosnia and Herzegovina and the region. Owing to the excellent sensory and physico-chemical characteristics and the very high concentration of biologically active ingredients, it is a very good potential for obtaining value added products or products with high content of bioactive, nutritionally and biologically valuable ingredients. The processing techniques of fresh fruit have a large influence on the content of bioactive components. The aim of this study was to analyse the effects of processing technologies of sour cherries on the content of bioactive compounds (total phenols, total flavonoids and anthocyanins) and the antioxidant capacity. Products that were analysed were juice, concentrate, extra jam and lyophilisate. The content of bioactive components and antioxidant capacity of these products was compared with fresh cherries. The results showed that the greatest influence on the content of bioactive ingredients has process where vacuum concentration is applied. More sophisticated technology such as lyophilization would contribute to the retention of bioactive components and could increase product competitiveness at the market.

A. Uzunović, S. Pilipović, A. Sapcanin, Z. Ademovic, B. Pilipović

Authors : Alija Uzunovic, Sasa Pilipovic, Aida Sapcanin, Zahida Ademovic, Berina Pilipović Abstract : Capsaicin is a naturally occurring alkaloid extracted from capsicum fruit extracts of different of Capsicum species. It has been employed topically to treat many diseases such as rheumatoid arthritis, osteoarthritis, cancer pain and nerve pain in diabetes. The high degree of pre-systemic metabolism of intragastrical capsaicin and the short half-life of capsaicin by intravenous administration made topical application of capsaicin advantageous. In this study, we have evaluated differences in the dissolution characteristics of capsaicin patch 11 mg (purchased from market) at different dissolution rotation speed. The proposed patch area is 308 cm2 (22 cm x 14 cm; it contains 36 μg of capsaicin per square centimeter of adhesive). USP Apparatus 5 (Paddle Over Disc) is used for transdermal patch testing. The dissolution study was conducted using USP apparatus 5 (n=6), ERWEKA DT800 dissolution tester (paddle-type) with addition of a disc. The fabricated patch of 308 cm2 is to be cut into 9 cm2 was placed against a disc (delivery side up) retained with the stainless-steel screen and exposed to 500 mL of phosphate buffer solution pH 7.4. All dissolution studies were carried out at 32 ± 0.5 °C and different rotation speed (50± 5; 100± 5 and 150± 5 rpm). 5 ml aliquots of samples were withdrawn at various time intervals (1, 4, 8 and 12 hours) and replaced with 5 ml of dissolution medium. Withdrawn were appropriately diluted and analyzed by reversed-phase liquid chromatography (RP-LC). A Reversed Phase Liquid Chromatography (RP-LC) method has been developed, optimized and validated for the separation and quantitation of capsaicin in a transdermal patch. The method uses a ProntoSIL 120-3-C18 AQ 125 x 4,0 mm (3 μm) column maintained at 600C. The mobile phase consisted of acetonitrile: water (50:50 v/v), the flow rate of 0.9 mL/min, the injection volume 10 μL and the detection wavelength 222 nm. The used RP-LC method is simple, sensitive and accurate and can be applied for fast (total chromatographic run time was 4.0 minutes) and simultaneous analysis of capsaicin and dihydrocapsaicin in a transdermal patch. According to the results obtained in this study, we can conclude that the relative difference of dissolution rate of capsaicin after 12 hours was elevated by increase of dissolution rotation speed (100 rpm vs 50 rpm: 84.9± 11.3% and 150 rpm vs 100 rpm: 39.8± 8.3%). Although several apparatus and procedures (USP apparatus 5, 6, 7 and a paddle over extraction cell method) have been used to study in vitro release characteristics of transdermal patches, USP Apparatus 5 (Paddle Over Disc) could be considered as a discriminatory test. would be able to point out the differences in the dissolution rate of capsaicin at different rotation speed.

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.

Z. Ademovic, S. Hodžić, Zarka Halilic-Zahirovic, D. Husejnagić, Jasna Džananović, B. Šarić-Kundalić, J. Suljagić

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.

Z. Ademovic, J. Salber, D. Klee

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.

1. 9. 2015.
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D. Miličević, Sanja Oručević Žuljević, Z. Ademovic

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.

Technologica Acta, Planjax Print Tešanj, Husejn Keran, M. Jašić, N. Juul, A. Odobašić, M. Salkić, Z. Ademovic et al.

Wild onion is a vegetable plant recognizable as food and folk medicine. Its greater application in the food and pharmaceutical industry has found in last decades. In food industry wild onion is mainly used as a spice, while in the pharmaceutical industry it is a common ingredient in dietary supplements. Processing of a fresh wild onion is constantly increasing. Active ingredients of wild onion are: raw vegetable fibers especially cellulose, allium compounds, chlorophyll, flavonoid, quercetin. Wild onion is used in a fresh and processed condition. In most cases it is processed by drying at 40-50 °C for 5 to 10 hours, but also the active ingredients are extracted with various technological processes. Water content in the final product ranges from 6 10% and water activity from 0,17 to 0,21. Total phenolic content was expressed as mg of gallic acid in 100 g of raw material and it was estimated as an average value 561,013. The antioxidant capacity was expressed as EC50 value that represents amount of sample required for the reduction of 50% DPPH free radicals and it was estimated as an average value 6,032. The content of the water was determined by drying. The water activity and color intensity were estimated by using instrumental methods. Antioxidant capacity was estimated by using of DPPH method and phenolic content by application of Folin-Ciocalteu calorimetry. Processing of fresh wild onion in the standardized dried semiproducts may be significant due to the conservation of biological properties, and possibility of applications in the food and pharmaceutical industries. Abbreviations: DPPH-2,2-diphenyl-1-picrylhydrazyl; EC50, concentration of antioxidant needed to reduce the original amount of radical by 50%.

S. Pilipović, B. Pilipović, A. Uzunović, A. Elezović, A. Boric, Z. Ademovic

Z. Ademovic, S. Marić, P. Kingshott, Z. Iličković

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.

Z. Ademovic, A. Gonera, P. Mischnick, D. Klee

Aminopropyl amyloses with various degrees of substitution (DS) were prepared and investigated with respect to their surface modification properties. Poly(acrylic acid) was grafted to plasma-activated PVDF films, and the functional amylose was bound via amide linkage formation. Layer formation was confirmed by X-ray photoelectron spectroscopy. Contact angle measurements and surface MALDI-TOF mass spectrometry indicated a hydrophilic surface and minimization of protein adsorption.

K. Bremmell, P. Kingshott, Z. Ademovic, B. Winther‐Jensen, H. J. Griesser

Interaction forces between surfaces designed to be protein resistant and fibrinogen (Fg) were investigated in phosphate-buffered saline with colloid probe atomic force microscopy. The surfaces of the silica probes were coated with a layer of fibrinogen molecules by adsorption from the buffer. The technique of low-power, pulsed AC plasma polymerization was used to make poly(ethylene glycol) (PEG)-like coatings on poly(ethylene teraphthalate) by using diethylene glycol vinyl ether as the monomer gas. The degree of PEG-like nature of the films was controlled by use of a different effective plasma power in the chamber for each coating, ranging from 0.6 to 3.6 W. This produced a series of thin films with a different number of ether carbons, as assessed by X-ray photoelectron spectroscopy. The interaction force measurements are discussed in relation to trends observed in the reduction of fibrinogen adsorption, as determined quantitatively by (125)I radio-labeling. The plasma polymer coatings with the greatest protein-repelling properties were the most PEG-like in nature and showed the strongest repulsion in interaction force measurements with the fibrinogen-coated probe. Once forced into contact, all the surfaces showed increased adhesion with the protein layer on the probe, and the strength and extension length of adhesion was dependent on both the applied load and the plasma polymer surface chemistry. When the medium was changed from buffer to water, the adhesion after contact was eliminated and only appeared at much higher loads. This indicates that the structure of the fibrinogen molecules on the probe is changed from an extended conformation in buffer to a flat conformation in water, with the former state allowing for stronger interaction with the polymer chains on the surface. These experiments underline the utility of aqueous surface force measurements toward understanding protein-surface interactions, and developing nonfouling surfaces that confer a steric barrier against protein adsorption.

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