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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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Effect of glucosyl sphingosine on the stratum corneum permeability
Bataalla, Omar Mahrous Farid ; Kováčik, Andrej (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of pharmaceutical technology Candidate: Omar Mahrous Farid Bataalla Supervisor: PharmDr. Andrej Kováčik, Ph.D. Consultant: Dr. Georgios Paraskevopoulos, PhD. Title of Thesis: Effect of Glucosyl Sphingosine on the stratum corneum Permeability Glucosyl sphingosine (GSP) belongs to a large lysolipid subclass of sphingolipids, which is formed from ceramide (Cer) precursors by its hydrolysis. Patients with some skin diseases, such as atopic dermatitis, have lower amounts of barrier Cer in comparison to a healthy skin. As a result, they have higher quantity of GSP with low moisture content due to impaired barrier function. The aim of my work was to investigate the effect of GSP on skin permeability (in this thesis, the uppermost epidermal layer, the stratum corneum, was used) by using four permeability markers, trans-epidermal water loss (TEWL), electrical impedance, flux of theophylline and flux of indomethacin. The electrical impedance showed higher permeability to ions in tissues with GSP (statistically significant) in comparison to the controls. An addition of GSP also increased the permeability to water, small polar molecules and large lipophilic molecules (both statistically insignificant). I also investigated the role of GSP on...
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The effect of the drying temperature on the properties of spray-dried lactose
Slezáčková, Jana ; 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: Jana Slezáčková Title of Thesis: The effect of the drying temperature on the properties of spray-dried lactose The aim of this work was to investigate the effect of inlet temperature on the physicochemical properties of spray dried lactose. 10% lactose solution was prepared by dissolving D-lactose monohydrate in distilled water and subsequently dried in a laboratory-scale spray drier. The inlet temperature of 130 řC - 200 řC was used. The physicochemical properties of lactose particles was investigated by optical microscopy and differential scanning calorimetry. Results indicated the influence of inlet temperature on particle size and shape and thermal properties of dried material. The morphology of spray-dried lactose showed tendency to higher sphericity when higher temperatures in a spray-drying process were used. Most of particles was in range 2,5 - 7,5 μm. The particles larger than 20 μm wasn't observed at the inlet temperature of 150 - 200 řC. At the inlet temperature over 150 řC the glass transition temperature was noticed. The glass transition temperature was observed around 24,8 - 63,5 řC. It was evident that higher drying temperature...
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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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Evaluation of compressibility of tableting mixtures containing theophylline using a compaction equation
Matyášová, Andrea ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department: Department of Pharmaceutical Technology Consultant: Doc. PharmDr. Zdeňka Šklubalová, Ph.D. Student: Andrea Matyášová Title of Thesis: Evaluation of compressibility of tableting mixtures containing theophylline using a compaction equation This thesis is aimed at the evaluation and comparison of excipients used in production of tablets. The compaction process of these excipients was evaluated using the parameters of the compaction equation. The mixtures of four fillers in various ratios were evaluated. These mixtures contained also theophylline as model drug and magnesium stearate as lubricant. The used three-exponential equation was previously developed by doc. RNDr. Milan Řehula, CSc. By using this compaction equation the volume reductions, speeds of volume reductions and consumed energies were calculated and evaluated. The results of this work showed that particular used fillers have different effect on the compaction process flow. That is caused primarily by different behavior of these materials during compaction and by formation of different types of bonds. Also the need of thorough cleaning and drying of compaction aid before compaction was confirmed.
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