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Preparation of spray-dried powder containing active substance, chitosan and surfactant
Kubová, Helena ; Svačinová, Petra (advisor) ; Smékalová, Monika (referee)
7 2 ABSTRACT Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Helena Kubová Title of Thesis: Preparation of spray-dried powder containing active substance, chitosan and surfaktant The main of this work was to prepare spray-dried powder containing meloxicam, chitosan and CTAB as surfactant. Spray drying is a method used to increase the bioavailability of poorly soluble drugs. Surfactants are substances that increase the solubility of drugs by the mechanism of micellar solubilization. Samples with different concentrations of meloxicam and constant amount of CTAB and chitosan used as a carrier were prepared. Three different temperatures, 170 řC, 190 řC and 210 řC were used for spray drying. The effectiveness of CTAB on properties of prepared particles and on the drug release from the samples was evaluated. The 1,4 mm diameter nozzle was used for spray drying. Optical microscopy and SEM were used to evaluate the appearance of prepared particles and the thermal characteristics were evaluated by DSC. The amount of drug released was evaluated using dissolution test. The particles of obtained powder had an irregular plate-like shape corresponding to chitosan particles. Spherical particles of meloxicam with CTAB...
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The influence of the die size on the compaction process
Marcinková, Nikola ; Ondrejček, Pavel (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Department of Pharmaceutical Technology Consultant: Mgr. Pavel Ondrejček, Ph.D. Student: Nikola Marcinková Title of Thesis: The influence of the die size on the compaction process This diploma thesis is focused on exploration the influence of the die size on the compaction process. That was evaluated by parameters of three-exponential equation. Compressibility was studied by using force-displacement record. In this work was also observed an effect of die size on the tensile strength. In processing the experimental part of this work were used four different model materials. Microcrystalline cellulose and dicalcium phosphate are used as model fillers and theophylline and paracetamol as model active substances. Compaction of these materials was carried out in dies of size 7 mm, 9 mm, 11 mm, 13 mm and 15 mm. The results of the work showed that the die size significantly affects all parameters force-displacement record. With the growing size of the die there was a reduction of energy parameters. Most of the compaction parameters were statistically influenced. Increasing die size caused reducing volume reduction and energy consumption and increased speed of volume reduction at the stage of pre- compression and elastic...
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Fractal aspects of flow and consolidation behaviour of microcrystalline cellulose.
Šofranková, Alexandra ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
7 2 Abstract Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Consultant: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Student: Alexandra Šofranková Title of Thesis: Fractal aspects of flow and consolidation behaviour of microcrystalline cellulose The object of this diploma thesis was to study the flow and consolidation characteristics of three types of microcrystalline cellulose. The granulometric characteristics, including the linear fractal dimension, were estimated using the optical microscopy. The bulk and tapped density, the angle of repose and the flow rate through an orifice of the hopper were evaluated. True density of the materials and the porosity of a loose powder bed were determined by helium pyknometry. The changes of density by the gravity consolidation were studied; the relationship of Hausner ratio on the number of taps describes best the differences in the consolidation behaviour of the substances. Modelling the consolidation kinetic by the exponential law allowed to determine the parameter N1/2, which shows the number of taps needed to reach one half of the powder volume reduction. The values of N1/2 within a range of 6,9-18 correlated well with the particle size of the used types of microcrystalline cellulose.
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Study of monolayer lipid models of skin barrier diseases
Doláková, Andrea ; Švecová, Barbora (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Author: Andrea Doláková Supervisor: PharmDr. Barbora Školová, Ph.D. Title of thesis: Study of lipid monolayer models of skin barrier diseases Skin protects human body from external factors and maintain internal integrity of organism. Skin barrier is formed by corneocytes and lipid matrix in intercellular space of stratum corneum, the uppermost layer of epidermis. Lipid matrix consists of ceramides, free fatty acids and cholesterol. The composition and organisation of lipid matrix are essential for the skin barrier properties. Ceramides are synthetized from glucosylated ceramide and sphingomyelin by hydrolitic enzymes β-glucocerebrosidase and sphingomyelinase. Insufficiency or malfunction of these enzymes lead to functionless skin barrier. The aim of this work was to prepare and study monolayer lipid models, which simulated the malfunction of sphingomyelinase in skin diseases. For valuation we used several techniques such as Langmuir monolayers, Brewster angle microscopy (at the air-liquid interface), Langmuir-Blodgett technique and atomic force microscopy. Monolayers with 100% substitution of sphingomyelin layout the most readily with rising surface pressure and the course of their isotherm is very...
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The effect of particle size on lactose compressibility
Havlíková, Natálie ; Ondrejček, Pavel (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Consultant: PharmDr. Pavel Ondrejček, Ph.D. Student: Natálie Havlíková Title of Thesis: The effect of particle size on lactose compressibility It is known that the particle size of the compressed material plays an important role in the manufacture of tablets. It affects the properties of intermediate and final products. In this thesis the properties of tablets made of two lactose types, which were used as model fillers, were studied. These were Tablettose® 80 and Lactopress® Anhydrous. In both lactose types, five sieved size fractions of the particle size ranging from 9 to 346µm and their original unsieved mixture were used. The compaction forces ranging from 2 to 10kN were used for tablet preparation. Magnesium stearate was used for external lubrication. The evaluation of the prepared tablets was done mainly by using the pharmacopoeial methods. The evaluated parameters were friability, disintegration time and hardness. Furthermore, the elasticity of the tablets and the evaluation using the force-displacement method parameters were assessed. From the results of this work, it is not possible to unambiguously determine the advantage of one particular fraction size in the comparison to the...
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The evaluation of the influence of lubricants on the compaction process of tableting mixtures with microcrystalline cellulose
Motlová, Tereza ; Svačinová, Petra (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Mgr. Tereza Motlová Title of Thesis: Evaluation of the influence of lubricants on the compaction process of tableting mixtures with microcrystalline cellulose This thesis evaluates the influence of various lubricants on the compaction process of tableting. Microcrystalline cellulose Avicel® PH 102 was used as filler. This cellulose was mixed with 2 % of magnesium stearate, Aerosil® 200, Syloid® AL-1 FP and Syloid® 244 FP EU, respectively. The evaluation was carried out using a compaction equation and stress relaxation tests. Parameters for evaluation of compaction equation were obtained by calculation from three-exponential equation. It is possible to determine the different phases of the compression process, its mechanism or to evaluate the compressed material using these parameters. The compression process is divided into three phases - pre-compression phase, the phase of elastic deformation and plastic deformation phase. The results show, that all lubricants accelerate the first stage of rearrangement of the particles and also the phase of elastic deformation. The speed of volume reduction in the phase of plastic deformation is similar...
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Study of the effect of cholesterol concentration on monolayer models
Šrámová, Eliška ; Paraskevopoulos, Georgios (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Author: Eliška Šrámová Supervisor: Dr. Georgios Paraskevopoulos, Ph. D Consultant: Mgr. Anna Nováčková Title of Thesis: Study of the effect of cholesterol concentration on monolayer models Skin is composed of 3 major layers: hypodermis, dermis, and epidermis. The uppermost layer, which is called stratum corneum (SC), has a unique structure resembling a well-built wall. Corneocytes represent bricks and the lipid matrix works like a mortar. Ceramides, free fatty acids, and cholesterol (Chol) are the main lipids creating the human SC matrix. In a healthy SC, the ratio of these lipids is equimolar. This ratio is crucial, not only to maintain the barrier function of the skin, but also for the organization of lipids in SC. Chol appears to be required for the correct lamellar organization, and the ordering of lipids inside of the lamellar formation (lateral organization) in SC. Abnormalities in the ratio of the lipids and depleted amount of Chol can lead to a disruption of the skin barrier function resulting in skin disease or multisystemic diseases (e.g. X-linked ichthyosis, Conradi-Hünermann-Happle syndrome, and CHILD syndrome.) The present work deals with a Chol deficiency study on lipid organization on...
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Evaluation of co-processed excipients intended for orodispersible tablets formulation
Vondrušková, Hana ; Svačinová, Petra (advisor) ; Vraníková, Barbora (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Co-processed excipients (CPE) can be defined as a combination of two or more substances, which are physically modified by an appropriate process (e.g. spray-drying). These excipients are currently increasingly used for production of tablets by direct compression. Due to the availability of a wide range of initial materials for their production, it is possible to obtain a large number of combinations with required characteristics and better properties than simple physical mixtures. Although the composition of these CPE may be similar, the small changes in the component's characteristics can make them behave differently after tableting. The aim of this work was a comparison of compressibility (using force- displacement record) of CPE (Starlac®, Combilac®, Cellactose 80®, DisintequikTM ODT® containing lactose and Ludiflash®, SmartEx QD 50®, SmartEx QD 100® containing mannitol) and properties of obtained tablets (tensile strength, friability, disintegration and water absorption ratio) prepared using compression pressures of 78, 130, 182 MPa. CPE containing lactose had lower values of plasticity compared with CPE containing mannitol but higher values of released elastic energy. This observation is also reflected in values of tensile strength...
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Lipid based nanoparticles: drug delivery platform
Voldřichová, Lenka ; Holas, Ondřej (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Supervisor: PharmDr. Ondřej Holas, Ph.D. Consultant: Mgr. Jana Kubačková Student: Lenka Voldřichová Title of thesis: Lipid based nanoparticles: drug delivery platform Lipic nanoparticles, as newly developed dosage forms, can overcome many drawbacks of conventional dosage forms. Their potential can be utilized in particular for prolonged, controlled and targeted release. They can also increase the bioavailability of drugs, especially those with poor solubility and also allow targeting, which causes increased accumulation of lipid nanoparticles in certain tissues compared to other tissues. nanoparticles suitable for drug encapsulation. The particles were prepared by the emulsion evaporation method. Their characterization was performed using a Zetasizer, which measured the particle size and the zeta potential. The properties of the formulations were evaluated in terms of nanoparticle size, polydispersity, zeta potential, and formulation properties. Differencial scanning calorimetry analysis was also performed on selected formulations. The selected final formulation was composed of 25 mg glycerol monostearate, 10 mg isopropyl myristate, 15 mg lecithin and Kolliphor P188 0,1% solution....
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Preparation of spray-dried lactose from high concentrated aqueous solutions
Souchová, Pavlína ; Svačinová, Petra (advisor) ; Vraníková, Barbora (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Pavlína Souchová Title of Thesis: Preparation of spray-dried lactose from high concentrated aqueous solutions In this work, the effect of higher concentration of lactose aqueous solution dried at different temperatures on the properties of spray-dried powder was evaluated. Lactose solutions with concentrations of 30 %, 40 % and 50 % were prepared for evaluation. Each solution was spray dried at three inlet temperatures: 180 řC, 200 řC and 220 řC. The geometrical characteristics of the obtained particles were evaluated by optical microscopy and thermal properties using differential scanning calorimetry (DSC). Based on the results, it was found that, compared to the original material (D-lactose monohydrate), spray-dried samples contained spherical particles with the smooth surface, which slightly decreased in size. Most of the particles were in the range of 2.5 to 15 μm. On the contrary, particles smaller than 2.5 μm and larger than 20 μm occurred in very small quantities. During spray drying, slight changes in particle size were observed as a function of the inlet temperature. DSC thermograms showed glass transition temperature, crystallization and...
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