In the frame of the project, industrial partner Helios d.d. employed in 2011 Dr. Lijiljana Ilić who obtained her PhD degree under mentorship of Full Prof. Dr. Željko Knez on Faculty of Chemistry and Chemical engineering.
F.03 Increased qualifications of the research and development staff
The invention is in the field of scanning electron microscopy and quality control of polymeric nanocomposite coatings. Solves the problem of sample preparation for the analysis of very thin polymer coatings thicker than 0.5 um, which are mixed in a very small particle diameter size from 10 nm to 100 nm, the so called nanoparticles, the method of scanning electron microscopy. The process used mounting conductive metal foil, which, together with the coatings placed in liquid nitrogen. Thicker coatings separated from film, fragile and broken analyzed. Thin coating of 3 micron does not distinguish from film, but only break brittle. In both cases, we are use the holder that allows pressure coating on both sides and stand up of the fracture surface.
F.33 Slovenian patentCOBISS.SI-ID: 16318230
The aim of the present research was to synthesize stable biodegradable aerogels used for controlled drug release of nicotinic acid and theophylline from the formulation. Two fundamental methods of ionic cross-linking were used to prepare alginate hydrogels: the diffusion method and the internal setting method. In the case of the first method cross-linkingis allowed by ion diffusion from a large outer reservoir into an alginate solution. Here single gel beads can be obtained. Also definite number of membranes was synthesized around spherical core to achieve even more controlled drug release. The influence of dug release from multi-membrane spherical aerogels was also studied dependent on alginate solution concentration and CaCl2 and BaCl2 concentration. Since alginate is ionic polysaccharide, the resultant alginate aerogel is expected to bind ionic drugs and release them slower. The effect of the number of membranes on model drugs nicotinic acid and theophylline loading and release was also investigated.
D.09 Tutoring for postgraduate studentsCOBISS.SI-ID: 16904726
Investigation of basic thermodynamical and transport data like phase equilibria, density, viscosity, dielectric constant and diffusion coefficient is fundamental for process design. Solubility of the substance in SC or SubC fluid and other fundamental data are crucial for economy of the process. The interaction of polymers with supercritical CO2 at elevated pressures is still under intensive research. Even if mathematical models can be used to predict the data at unmeasured conditions, these parameters should be determined experimentally to find the suitable model and to confirm the fitting of the results to the model. The aim was to determinate the solubility and the diffussion rate of the binary system polyethylene glycol/CO2 (with different molar masses) with two different methods in pressure range from 10.0 MPa up to 40.0 MPa at a temperature of 343 K. A set of experiments on system polyethylene glycol/CO2 was measured using a method developed by the authors. Results were then compared to data obtained by a well established, precise method using MSB (Magnetic Suspension Balance) at same process conditions in order to validate our results.
F.18 Transfer of new know-how to direct users (seminars, fora, conferences)COBISS.SI-ID: 16730134
In the present study we have evaluated the degradation behaviour of poly(lactide-co-glycolide) in a simulated body fluid, before and after foaming with supercritical CO2. Initial polymer samples, shaped as tablets, and foamed samples were immersed in Sörensen buffer solution and maintained for 10 weeks at a constant temperature of 37°C under mild stirring. Every week samples of degradation medium were collected from each test vial and various tests were performed. The pH of each liquid sample was measured, while precipitation with excess ethanol was used to identify the dissolved polymer. The mass loss of samples at various stages of the study was also determined. A comparison was performed between the in vitro behaviours of PLGA samples before and after supercritical fluid processing. It was observed that PLGA foams degrade slightly slower than the tablets. These data are important for evaluating the suitability of various processing methods when designing biodegradable medical devices or implants with well-defined requirements regarding their stability and mechanical properties during specific applications.
F.18 Transfer of new know-how to direct users (seminars, fora, conferences)COBISS.SI-ID: 17855254