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Estimation of mechanical properties of thin films using numerical modelling of experimental tests
Tinoco Navarro, Hector Andres ; Jančo,, Roland (referee) ; Klusák,, Jan (referee) ; Hutař, Pavel (advisor)
Testování tenkých filmů pomocí "Bulge testu" je experimentální technika která zahrnuje použití numerických a analytických přístupů k charakterizaci mechanických vlastností tenkých vrstev. Tato práce se zabývá některými omezeními nalezenými v klasických modelech, které popisují chování tenkých vrstev podrobených tomuto testu. Za tímto účelem byly vyvinuty nové modely a numerické strategie pro stanovení různých mechanických vlastností jednovrstvých a dvouvrstvých tenkých vrstev za odlišných strukturních podmínek, jako je elasticita, plasticita a lom. Kombinací metody konečných prvků a klasických analytických řešení byly navrženy a ověřeny různé metodiky pro výpočet elastických vlastností (E a v), zbytkových napětí, meze kluzu a lomové houževnatosti. Mechanické vlastnosti filmů z nitridu křemíku, hliníku a zlata byly charakterizovány pomocí experimentálních dat o zatížení-průhybu získaných z měření. Stanovené vlastnosti vykazovaly uspokojivou shodu s což potvrdilo, že metody navržené v této práci mohou být užitečné pro odhad mechanických vlastností se známými materiálovými vlastnostmi tenkých vrstev.
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Dissolution of a drug from thin films based on plasticized PLGA derivatives
Kodytková, Simona ; Šnejdrová, Eva (advisor) ; Paraskevopoulou, Anna (referee)
CHARLES UNIVERSITY Faculty od Pharmacy in Hradec Kralove Department od Pharmaceutical Technology Author: Simona Kodytková Title od Diploma thesis: Dissolution of a drug from thin films based on plasticized PLGA derivatives Supervisor: PharmDr. Eva Šnejdrová, Ph.D. The aim of the presented work was to formulate liquid systems for the formulation of in situ thin films (FFS) based on copolymers D,L-lactic and glycolic acid (PLGA) and to study the effect of a combination of salicylic acid and methyl salicylate in film and the effect of their various concentrations on dissolution profiles. The theoretical section summarizes the general knowledge about the characteristics, substances used to formulate FFS and methods for their testing. In the experimental section, liquid systems forming in situ films by solvent evaporation were prepared, based on a linear or branched PLGA polymer containing salicylic acid as a poor water soluble drug, and methyl-salicylate as a multifuctional plasticizer, at different concentrations. The solubility test of salicylic acid, methyl salicylate and their mixtures, and dissolution tests of drug and plasticizer in phosphate buffer buffer pH 5.5 at 37 řC were performed. Salicylate analysis was performed by HPLC. Based on the results, it can be stated that faster dissolution of...
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Preparation of the human skin barrier model using thin lipid film deposition
Suciu-Šubert, Karina ; Pullmannová, Petra (advisor) ; Opálka, Lukáš (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Student: Karina Suciu-Šubert Supervisor: Mgr. Petra Pullmannová, Ph.D. Title of diploma thesis: Preparation of the human skin barrier model by using thin lipid film deposition The uppermost part of the human skin - the stratum corneum, which protects the body from the external environment, is made up of cornified cells - corneocytes, which are surrounded by the extracellular matrix of highly ordered lipids: ceramides (Cer), fatty acids and cholesterol. The protective barrier is constantly renewed with so-called keratinocytes, which differentiate to corneocytes and finally desquamate from skin to surface. The corneocyte envelope replaces plasma membrane of corneocytes. It consists of proteins (eg. involucrin) and a lipid monolayer consisting mainly of ω-hydroxyceramides which are attached to the protein segments by covalent bonds. The task of this diploma thesis was the preparation of the human skin barrier model by using thin lipid film deposition. Two different lipid mixtures were based on Cer NS or Cer EOS and NS. The mixtures were applied on the hydrophilic or hydrophobic substrate by spraying with Linomat V. The amount of lipids and consequently the number of theoretical lipid layers on the...
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