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Development of liquisolid systems for colon targeting
Ogadah, Chiazor Ugo ; Vraníková, Barbora (advisor) ; Zámostný, Petr (referee) ; Gajdziok, Jan (referee)
Univerzita Karlova, Farmaceutická Fakulta V Hradci Králové Školicí pracoviště: Katedra Farmaceutické Technologie Doktorský studijní program: Farmaceutická Technologie Kandidátka: Mgr. Chiazor Ugo Ogadah Školitelka: doc. PharmDr. Barbora Vraníková, Ph.D. Konzultantka: doc. Prof. PharmDr. Zdeňka Šklubalová, Ph.D. Název dizertační práce: Vývoj liquisolid systémů s cíleným přívodem léčiva do kolonu V lokální nebo systémové terapii chorob tlustého střeva mají systémy cílící do kolonu slibnou perspektivu. Úspěch však představuje výzvu díky fyziologickým bariérám trávicího traktu. Pokud zvýšení rozpustnosti léčiva předchází cílení, lze rozpouštění, jako krok limitující rychlost, obejít, urychlit vstřebání léčiva a zvýšit jeho perorální biodostupnost. Pro optimalizaci dávky a terapeutického efektu je kromě toho potřebné zadržet přípravek v místě cílení. Cílem této práce je proto vývoj systému pro doručení a cílení omezeně rozpustného léčiva cyklosporinu A (CyA) do kolonu. V první části experimentu byly využity preformulační studie k dosažení zvýšené rozpustnosti a zrychleného uvolnění CyA pomocí tzv. liquisolid sytému (LSS) nebo přípravou interaktivních směsí společným mletím (komletím). To zahrnovalo výběr vhodného nosiče a hodnocení jeho vlastností při mletí, stejně jako výběr netěkavého...
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Influence of lubricants on viscoelastic parameters of compaction process
Svačinová, Petra ; Rabišková, Miloslava (advisor) ; Kubová, Kateřina (referee) ; Zámostný, Petr (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department Pharmaceutical technology Candidate Mgr. Petra Svačinová Supervisor Prof. PharmDr. Miloslava Rabišková, CSc. Title of Doctoral Thesis Influence of lubricants on viscoelastic parameters of compaction process This thesis deals with an evaluation of lubricant's influence on viscoelastic parameters of compaction process. The force-displacement record and stress relaxation test were used for this evaluation. This study evaluates the viscoelastic parameters on three fillers intended for direct compression, i.e. microcrystalline cellulose Avicel PH-200, lactose Lactochem Fine Crystals and calcium hydrogen phosphate dihydrate Emcompress. Magnesium stearate and modified colloidal silica Syloid were used as lubricants at concentrations of 0.5 % and 1 %. Particle size and shape and specific surface area were determined for all used excipients. Flow properties were studied for individual fillers and also for their mixtures with lubricants. Subsequently, tablets were compressed from fillers and mixtures using force-displacement record and stress relaxation test, and viscoelastic parameters were evaluated. The applied compression forces for both methods were 5 kN, 10 kN and 15 kN. The hardness of tablets was measured. The results show...
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Study of flow and consolidation behaviour of binar mixtures of Cellets and filler for preparation of multilayer tablets
Jarolímová, Žofie ; Šklubalová, Zdeňka (advisor) ; Franc, Aleš (referee) ; Zámostný, Petr (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Candidate Mgr. Žofie Jarolímová Supervisor doc. PharmDr. Zdeňka Šklubalová, Ph.D. Title of Doctoral Thesis Study of flow and consolidation behaviour of binary mixtures of Cellets and filler for preparation of multilayer tablets The manufacture and quality of solid dosage forms is influenced mainly by flow, consolidation and compaction properties of powder excipients. In this work, the behaviour of pellets made of microcrystalline cellulose (cellets), which might be used as a drug carrier in multilayer tablets, and their binary mixtures with microcrystalline cellulose was studied. More than 20 powder excipients commonly used in tablet production and their binary mixtures were involved in preliminary studies. Measuring of the angle of repose, Hausner ratio and the mass flow rate through a hopper orifice was influenced by the particle shape, size and the width of the particle size distribution. In order to identify easily the free flowing substances, the hopper orifice having 10 mm diameter was useful. Excellent flow properties were confirmed for cellets with conventional testing methods thanks to their spherical shape and narrow particle size distribution. The avalanche testing using a rotational drum...
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Study of flow and consolidation behaviour of binar mixtures of Cellets and filler for preparation of multilayer tablets
Jarolímová, Žofie ; Šklubalová, Zdeňka (advisor) ; Franc, Aleš (referee) ; Zámostný, Petr (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Candidate Mgr. Žofie Jarolímová Supervisor doc. PharmDr. Zdeňka Šklubalová, Ph.D. Title of Doctoral Thesis Study of flow and consolidation behaviour of binary mixtures of Cellets and filler for preparation of multilayer tablets The manufacture and quality of solid dosage forms is influenced mainly by flow, consolidation and compaction properties of powder excipients. In this work, the behaviour of pellets made of microcrystalline cellulose (cellets), which might be used as a drug carrier in multilayer tablets, and their binary mixtures with microcrystalline cellulose was studied. More than 20 powder excipients commonly used in tablet production and their binary mixtures were involved in preliminary studies. Measuring of the angle of repose, Hausner ratio and the mass flow rate through a hopper orifice was influenced by the particle shape, size and the width of the particle size distribution. In order to identify easily the free flowing substances, the hopper orifice having 10 mm diameter was useful. Excellent flow properties were confirmed for cellets with conventional testing methods thanks to their spherical shape and narrow particle size distribution. The avalanche testing using a rotational drum...
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Study of static and dynamic flow properties of pharmaceutical excipients
Hurychová, Hana ; Šklubalová, Zdeňka (advisor) ; Vetchý, David (referee) ; Zámostný, Petr (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Pharmaceutical Technology Candidate: Ing. Hana Hurychová Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Title of Doctoral Thesis: Study of static and dynamic flow properties of pharmaceutical excipients Flow properties are among the most significant characteristics of pharmaceutical materials. Recent modern technologies allow preparation of particles with modified surface properties and flow behaviour for the conventional as well as new excipients. In this work, the static (compressibility index, Hausner ratio, angle of repose, shear testing) and dynamic (flow rate, avalanche testing) flow properties of a wide variety of excipients, their particle size fractions and selected model mixtures were evaluated. In particular, attention was paid to modelling of the flow rate by the equation prospectively suitable for use in the standardization of flow testing in pharmaceutical technology. The power equation in which the equation parameter is a direct prediction of the flow rate through an orifice having a unit diameter is recommended. The basic granulometric characteristics of particles were completed with the particle fractal dimension (pDF) and the bulk fractal dimension (bDF). Although a relatively strong correlation between the...
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Breaking of Rod-shaped Model Material during Compression.
Kulaviak, Lukáš ; Pěnkavová, Věra ; Růžička, Marek ; Punčochář, Miroslav ; Zámostný, P. ; Grof, Z. ; Štěpánek, F. ; Schöngut, M. ; Havlica, Jaromír
The breakage of a model anisometric dry granular material caused by uniaxial compression was studied. The bed of uniform rod-like pasta particles (8 mm long, aspect ratio 1:8) was compressed (Gamlen Tablet Press) and their size distribution was measured after each run (Dynamic Image Analysing). The compression dynamics was recorded and the effect of several parameters was tested (rate of compression, volume of granular bed, pressure magnitude and mode of application). Besides the experiments, numerical modelling of the compressed breakable material was performed as well, employing the DEM approach (Discrete Element Method). The comparison between the data and the model looks promising.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22018011012170 - PDF
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Powder Rheology of Nanocrystalic Particles.
Kulaviak, Lukáš ; Pěnkavová, Věra ; Růžička, Marek ; Punčochář, Miroslav ; Zámostný, P. ; Grof, Z. ; Štěpánek, F. ; Schöngut, M. ; Havlica, Jaromír
Pigments are mostly nanometric powder of anisometric particles providing complex rheological behaviour. The interparticle forces of grains (> 100 μm) are based on direct contact, which is mainly influenced by the particle size and shape. On the other hand powder (< 4 μm) and especialy nanometric powder (< 100 nm) is influenced mainly by electrostatic charges and by moisture (respectively by the liquid and solid bridges forming). However the morphology affects the surface area and thus the distribution of surface charge and\nthe moisture content on/in single particle. Last but not least, it is also good to know the history of the powder, i.e. the effect of aging and the memory of the powder on the strength of the material. The nanometric powder TiO2 was chosen as a demonstration material and measuring device was FT4 powder rheometer.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22018011012520 - PDF
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Influence of lubricants on viscoelastic parameters of compaction process
Svačinová, Petra ; Rabišková, Miloslava (advisor) ; Kubová, Kateřina (referee) ; Zámostný, Petr (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department Pharmaceutical technology Candidate Mgr. Petra Svačinová Supervisor Prof. PharmDr. Miloslava Rabišková, CSc. Title of Doctoral Thesis Influence of lubricants on viscoelastic parameters of compaction process This thesis deals with an evaluation of lubricant's influence on viscoelastic parameters of compaction process. The force-displacement record and stress relaxation test were used for this evaluation. This study evaluates the viscoelastic parameters on three fillers intended for direct compression, i.e. microcrystalline cellulose Avicel PH-200, lactose Lactochem Fine Crystals and calcium hydrogen phosphate dihydrate Emcompress. Magnesium stearate and modified colloidal silica Syloid were used as lubricants at concentrations of 0.5 % and 1 %. Particle size and shape and specific surface area were determined for all used excipients. Flow properties were studied for individual fillers and also for their mixtures with lubricants. Subsequently, tablets were compressed from fillers and mixtures using force-displacement record and stress relaxation test, and viscoelastic parameters were evaluated. The applied compression forces for both methods were 5 kN, 10 kN and 15 kN. The hardness of tablets was measured. The results show...
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