National Repository of Grey Literature 229 records found  beginprevious117 - 126nextend  jump to record: Search took 0.01 seconds. 
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...
A study of compressiblity and properties of tablets from coprocessed dry binder with manntol and croscarmellose sodium for orodispersible tablets.
Kamarýtová, Martina ; Mužíková, Jitka (advisor) ; Šklubalová, Zdeňka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Pharmaceutical Technology Student: Martina Kamarýtová Consultant: PharmDr. Jitka Mužíková, Ph.D. Title of the Diploma Thesis: A study of compressibility and properties of tablets from coprocessed dry binder with mannitol and croscarmellose sodium for orodispersible tablets. This thesis deals with the study of directly compressible tableting materials and tablets with Parteck® ODT, which is designed for orodispersible tablets. The effect of three lubricants on the properties of tableting materials and tablets is evaluated. Tested lubricants are magnesium stearate, calcium stearate and sodium stearyl fumarate in concentrations of 0,5 and 1 %. Flow properties, compressibility, ejection force, tensile strength and disintegration time of tablets are tested. The compressibility is evaluated by the energy profile of compression process. Lubricants did not improve the flowability of Parteck® ODT. The total energy of compression increased with compression force and highest values were at the tableting material with 0,5 % magnesium stearate. The values of plasticity decreased with compression force, highest values were at the tableting material with 0,5 % sodium stearyl fumarate. The ejection force increased with compression force, the...
Study of bulk and consolidation properties of size fractions of anhydrous lactose
Dostálová, Eliška ; Šklubalová, Zdeňka (advisor) ; Mužíková, Jitka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Ing. Hana Hurychová Student: Eliška Dostálová Title of Thesis: Study of bulk and consolidation properties of size fractions of anhydrous lactose The bulk and consolidation behaviour of pharmaceutical excipients belong to their important properties. Properties of five size fractions of anhydrous lactose having the particle size in the range of 1-400 µm were studied in this thesis. The measurement was carried out by using static and dynamic pharmacopoeial methods. The bulk density and the tapped density, the angle of repose were evaluated as well as the true density of particles by using the gas pycnometry. The mass flow rate through the orifice of a model conical hopper by the force of gravity was estimated for the individual size fractions. The discharge rate through the orifice having the diameter in a range of 0.6-1.5 cm was modelled with the Beverloo et al and Jones & Pilpel power regression equations; the precision of the flow rate prediction was about 3 %. The best bulk properties were detected for the particle size fraction 246 µm. The results of the evaluation of the consolidation dynamic during the tapping of powder bed permitted...
Homogenization of powder blends using a high-speed mixer
Perďochová, Kristína ; Šklubalová, Zdeňka (advisor) ; Mužíková, Jitka (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Department of Pharmaceutical Technology Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: PharmDr. Karel Palát, CSc. Student: Kristína Perďochová Title of Thesis: Homogenization of powder blends using a high-speed mixer This work focuses on using a high-speed mixer for the powder mixing process in pharmaceutical technology. Shortened experimental plan was used to study the influence of three factors (mixing speed, mixing time and weight of the mixture) in order to achieve the overall homogenity of the mixture containing acetylsalicylic acid and microcrystalline cellulose. Individual samples were compressed into tablets. The homogenity of the mixture was evaluated using near infrared spectroscopy (NIR). The standard devations of the measured spectra were observed. The best results obtained from studied mixtures were achieved by a combination of mixing 150 g of mixture, rotational speed of 900 rpm and mixing time of 30 seconds.
Optimization of tablet coating.
Brokešová, Jana ; Mrvová, Zdenka (advisor) ; Šklubalová, Zdeňka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Supervisor: Consultant: Ing. Zdenka Mrvová Mgr. Matěj Kovář Student: Jana Brokešová Title of Thesis: Optimization of tablet coating Tablet coating represents an important procedure in pharmaceutical technology. The coating can protect an active pharmaceutical ingredient from negative environmental conditions as well as ensure the drug release at a specific time and a specific site in the organism. Generally, the main types of tablet coating are sugar and film coating. As the sugar coating has a number of disadvantages such as a time-consuming production process, the difficult process standardization, the impossibility to produce a modified release mechanism, is nowadays rarely being used in pharmaceutical companies. This work deals with the replacement of sugar coating with film coating technology for the multivitamin product Spofavit®. During the pilot batch, the commercial coating mixture Nutraficient® Food Supplement Coating, Opadry AMB was applied on two types of tablet cores: the original composition tablet cores and the modified ones with added lactose. The weight variation, hardness, friability and disintegration properties were tested. After processing the results of the pilot batch, a...
Evaluation of dissolution profile of suppositories containing diclofenac sodium salt
Stašková, Zuzana ; Ondrejček, Pavel (advisor) ; Šklubalová, Zdeňka (referee)
CHARLES UNIVERSITY Faculty of Pharmacy in Hradec Králové Departement of Pharmaceutical Technology Student: Zuzana Stašková Title: Evaluation of dissolution profile of suppositories containing diclofenac sodium salt Consultant: PharmDr. Pavel Ondrejček, Ph.D. Suppositories are a promising dosage form, which is advantageously used in cases where it is not possible to use other dosage form (e.g. in children, non-cooperating patients or patients with swallow inability). Dissolution tests serve both as qualitative tests of medicinal products and on the other hand, provide valuable information during formulation of new ones. The aim of this work was to study the dissolution process of diclofenac sodium from suppositories. The theoretical part focuses on the description of dissolution methods, the preparation of suppositories and the active substance used. The tested suppositories were prepared by three methods (manually, by Unguator technology and industry made ones), in experimental part. All suppositories contained 100mg of the active ingredient suspended in the solid fat base. Dissolution tests for lipophilic solid dosage forms by flow-through apparatus containing suppository cell according to the Czech Pharmacopoeia were performed at three media flow rates. It was found that the maximum release of...
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.
Study of consolidation behaviour of lactose and its blends
Bérešová, Michaela ; Šklubalová, Zdeňka (advisor) ; Vraníková, Barbora (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Student: Michaela Bérešová Title of Thesis: Study of consolidation behaviour of lactose and its blends Flow behaviour and consolidation properties are important characteristics of the powder substances. The aim of this thesis was to evaluate these properties for four types of lactose with different particle size and for the mixtures of two lactoses with different flow properties. The density and porosity of the powder bed and their changes during the consolidation due to the gravitational tapping were studied. The non-linear regression equation was used to describe the consolidation process for the samples and the parameter N½, which expresses the number of taps needed to achieve a half reduction of a powder bed volume. The value of N½ increased with the decrease in the particle size.
A study of directly compressible tableting materials and tablets with the coprocessed dry binder containing lactose, povidone and crospovidone.
Nguyen Thi, Thu Ha ; Mužíková, Jitka (advisor) ; Šklubalová, Zdeňka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Pharmaceutical technology Student: Nguyen Thi Thu Ha Consultant: PharmDr. Jitka Mužíková, Ph.D. Title of the Diploma Thesis: A study of directly compressible tableting materials and tablets with the coprocessed dry binder containing lactose, povidone and crospovidone. Thesis studies the coprocessed dry binder Ludipress® , which consists of α-lactose monohydrate, polyvinylpyrrolidone and crospovidone. Ludipress® was tested in the mixture with lubricants magnesium stearate and sodium stearyl fumarate in 0,5 % and 1 % concentration and with microcrystalline cellulose in 25 % concentration. Test focused on flowability, compressibility, tensile strength and disintegration time of tablets. Compressibility was evaluated by energy profile of compression in function of compression force. Ludipress® shows high friction therefore addition of lubricant is necessary. Lubricants improved powder flowability and compressibility; 0,5 % concentration of magnesium stearate is the most suitable. Higher concentration of lubricants decreased tensile strength of tablets. Disintegration time did not increase with compression force. Tablets with 1 % concentration of sodium stearyl fumarate had the longest time of disintegration. The addition of 25 %...
Study of Effect of Ceramide Hydroxylation on Permeability and Microstructure of Model Lipid Membranes
Kováčik, Andrej ; Vávrová, Kateřina (advisor) ; Uhriková, Daniela (referee) ; Šklubalová, Zdeňka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Department of Organic and Bioorganic Chemistry Candidate Mgr. Andrej Kováčik Supervisor prof. PharmDr. Kateřina Vávrová, Ph.D. Title of Doctoral Thesis Study of Effect of Ceramide Hydroxylation on Permeability and Microstructure of Model Lipid Membranes Ceramides (Cer) occur in intracellular spaces of the stratum corneum, the outermost mammalian epidermal layer, where they along with other lipids (free fatty acids, cholesterol) form a skin lipid barrier. Besides sphingosine- (Cer NS) and dihydrosphingosine-based Cer (Cer NdS), in the healthy mammalian epidermis some polar Cer are present, i.e., Cer based on phytosphingosine (with hydroxyl group in position 4, i.e., phytoceramides) and Cer based on 6-hydroxysphingosine (with hydroxyl group in position 6, i.e., 6- hydroxyceramides). However, the role of phytoceramides (Cer NP) and 6 hydroxyceramides (Cer NH) in the skin barrier function has not been clarified. Moreover, 6 hydroxyceramides are not commercially available. Therefore, the first aim of this work was to synthesize physiological 6-hydroxyceramides. The synthesis of 6- hydroxylated Cer, i.e., Cer NH with long (C24:0) and Cer EOH with ultralong acyl with ester-linked linoleic acid is reported. The triple bond was reduced...

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