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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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Design of chemically resistant coatings using secondary raw materials and hazardous waste
Stodolovská, Šárka ; Jakubík, Aleš (referee) ; Drochytka, Rostislav (advisor)
On the basis of theoretical knowledge gained from Czech and foreign technical literature, two types of coatings using fillers based on secondary raw materials, including hazardous waste, is designed and experimentally verified. The expected use of the proposed coating systems, both PREMIUM and ECOLOGY, is the protection of building structures that are permanently stressed by increased chemical stress. When designing the PREMIUM coating material, emphasis is primarily focused on chemical resistance and functional parameters, and the ecological performance of the raw materials used is monitored primarily with the ECOLOGY coating material. In both cases, it is important to maintain a favorable price / value ratio.
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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 effect of rice extract on the compressibility and mechanical properties of microcrystalline cellulose tablets.
Rumlerová, Lenka ; Ondrejček, Pavel (advisor) ; Mužíková, Jitka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Department of Pharmaceutical Technology Consultant: PharmDr. Pavel Ondrejček, Ph.D Student: Lenka Rumlerová Title of Thesis: The effect of rice extract on the compressibility and mechanical properties of microcrystalline cellulose tablets. This thesis deals with influence of rice extract, as a new kind of glidant on compressibility of microcrystalline celulose as a model filler. Furthermore it evaluates the impact of rice extract on tablet properties. Effects of rice extract were compared with two standard glidants - magnesium stearate and colloidal silicon dioxide. As first the influence of diferent glidants concetrations on flow properties of mixtures were assesed. Tablets were compresed using three different compression forces. A force- displacement record was used to evaluate the compressibility of microcrystalline cellulose and its mixtures with glidants. Subsequently, the properties of tablets were evaluated. The radial strenght, abrasion, and tablet disintegration time were measured. The results revealed that the rice extract has the least effect on mixtures flow poperties. However, all mixtures showed a statistically significant improvement in flowability. When using a 1 % rice extract, the flow properties of the...
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Dissolution testing of tablets containing theophylline and mixtures of two types of calcium hydrogen phosphates and microcrystalline cellulose
Vávrová, Kateřina ; 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: Kateřina Vávrová Title of Thesis: Dissolution testing of tablets containing theophylline and mixtures of two types of calcium hydrogen phosphates and microcrystalline cellulose The aim of this thesis was the dissolution testing of tablets containing theophylline, the mixture of two dicalcium phosphate types and microcrystalline cellulose. The influence of tablet composition on the dissolution profiles was evaluated. The tablets were prepared from the mixtures containing microcrystalline cellulose, dicalcium phosphate anhydrous and dihydrate. These substances were used as fillers. Prepared mixtures contained theophylline as a model active ingredient and magnesium stearate as lubricant. Afterwards, the dissolution tests were done. For these tests, the basket method was utilized. As a dissolution medium the 0,1M hydrochloric acid solution was used. From the results of this experiment we concluded that we can influence the total amount of released theophylline and the speed of its release by the different ratio of microcrystalline cellulose and one of dicalcium phosphate types. The fastest theophylline dissolution was in tablets with high...
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Evaluation of elastic recovery of tablets containing theophylline
Vitverová, Barbora ; Šklubalová, Zdeňka (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: Doc. PharmDr. Šklubalová Zdeňka, Ph.D. Student: Barbora Vitverová Title of Thesis: Evaluation of elastic recovery of tablets containing theophylline This diploma thesis deals with evaluation of elastic recovery of tablets containing theophylline. The axial and radial elastic recovery is evaluated. Used materials are characterized in a theoretical part. It concerns microcrystalline cellulose Comprecel 102, lactose SpheroLac 100, calcii hydrogenphosphas anhydrous Di- Cafos A150, calcii hydrogenphosphas dihydrate Di-Cafos D160, magnesii stearas and theophylline. Further, compression process and its evaluation are described and also the elastic recovery of tablets after compression, its calculation and factors which can influence it. The experimental part of thesis deals with the elastic recovery of tablets. The tablets were compressed by compression strength 10 kN and the height and diameter were measured after 0, 3, 6 and 24 hours after compressing. The elastic recovery of tablets was calculated from these values. The dimensions of tablets at the maximal compression strength 10 kN were used as the initial values. From results is obvious that the highest elastic recovery is...
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Measurement of stress relaxation of mixtures of microcrystalline cellulose and calcium hydrogen phosphate intended for the preparation of tablets with theophylline
Hofmanová, Markéta ; Šklubalová, Zdeňka (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Doc. PharmDr. Sklubalova Zdenka, Ph.D. Student: Marketa Hofmanova Title of Thesis: Measurement of stress relaxation of mixtures of microcrystalline cellulose and calcium hydrogen phosphate intended for the preparation of tablets with theophylline The powder mixtures with theophylline were studied from the aspect of viscoelastic properties of used materials and tablets tensile strength. In the theoretical part the thesis concerned with description of materials which were used in the mixtures. They are: Microcrystalline cellulose Comprecel 102, calcium hydrogen phosphate anhydrate Di-Cafos A150, calcium hydrogen phosphate dihydrate Di-Cafos D160 and lactose SpheroLac 100. The thesis also deals with the stress relaxation test. The stress relaxation test, its evaluation by several methods and its use in the pharmacy and in different fields are described. The experimental part deals with viscoelastic characteristics of the mixtures. These characteristics were evaluated by stress relaxation test with maximal compression force 10 kN and dwell time 180 s. Also the tensile strength was evaluated. The highest values of parameters of elasticity A1-3 and plasticity P1-3 were measured in...
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Determination of flow properties of mixtures for preparation of tablets containing theophylline
Brunettová, Monika ; Šklubalová, Zdeňka (advisor) ; Mužíková, Jitka (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: Doc. PharmDr. Šklubalová Zdeňka, Ph.D. Student: Brunettová Monika Title of Thesis: Determination of flow properties of mixtures for preparation of tablets containing theophylline The aim of this diploma thesis was to characterize the flow properties and moisture content of mixtures for preparation of tablets containing theophylline. Parameters were monitored depending mainly on the content of the fillers, that were dicalcium phosphate, microcrystalline cellulose and lactose. Twenty-five prepared mixtures with different ratios of these fillers were evaluated. Flowability was evaluated by three methods stated in Czech Pharmacopoeia 2009 - compressibility index and Hausner ratio, flow through an orifice and angle of repose. Moisture content was evaluated as a weight loss during drying. Mixtures containing dicalcium phosphate and lactose proved more appropriate in terms of flowability, their flow properties are passable. However, according to the moisture content, mixture with microcrystalline cellulose are more preferable.
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Determination of the compressibility of excipients used for formulation of tablets with theophylline.
Kousoulidou, Viktoria ; Šklubalová, Zdeňka (advisor) ; Ondrejček, Pavel (referee)
1 Abstract Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: Assoc. Prof. PharmDr. Zdenka Sklubalova, Ph.D. Student: Viktoria Kousoulidou Title of Thesis: Determination of the compressibility of excipients used for formulation of tablets with theophylline The current thesis is focused on the compressibility properties of five powders used in tablet formulation: Comprecel, Spherolac, DI-CAFOS D160, DI-CAFOS A150 as excipients and Theophylline as the active substance. The particle size, moisture content, bulk density and flowability of the powders are determined. The powders are compressed and the results are evaluated by means of the parameters of the compaction equation and the force-displacement method (compression under 5, 10, 15 kN). Then, the crushing strength of tablets prepared from each powder by the force-displacement method is measured. The average values of the crushing strength are used to calculate the tensile strength of the tablets. Best compressibility is found in Comprecel and Theophylline with tensile strength values of 1.31 MPa under 5 kN, 3.31 MPa under 10 kN, 4.75 MPa under 15 kN and 1.02 MPa under 5 kN, 2.27 MPa under 10 kN, 3.09 MPa under 15 kN, respectively.
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