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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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Effect of paracetamol on the parameters of compression equation
Mařanová, Lucie ; Řehula, Milan (advisor) ; Ondrejček, Pavel (referee)
Evaluation of the tableting mixtures containing the paracetamolum by the parameters of the equation of compression The diploma thesis deals with effect of paracetamol on the parameters of compression equation. These parameters characterize compression process in the individual phases of compression: precompression phase, phase of elastic deformation and phase of plastic deformation. Paracetamolum was studied in the five mixtures, where it occurred in different ratio with microcrystalline cellulose. Looseness, Carr's index and Hausner ratio were evaluated for each mixture. The sizes of reductions ai, sizes of energies Ei and Ri, "half-pressures" pHi and the velocity constants 1/ti were calculated using three-exponential equation of compression for the individual phases of pressing. The results showed poor flow properties of tableting mixtures and thus its unsuitability for direct compression. The results of the study have revealed that increasing amounts of paracetamolum in the mixture increase reduction of volume a1 and velocity of volume change 1/t1 in dependence on the amount of the extruded air and decrease the required energy due to the smooth surface and less friction during the precompression phase. Reduction of volume a2 decrease with the increase of content of paracetamol due to...
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Evaluation of tensile strength of tablets containing theophylline
Janoutová, Hana ; Šklubalová, Zdeňka (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: Doc. PharmDr. Zdeňka Šklubalová, Ph.D. Student: Hana Janoutová Title of Thesis: Evaluation of tensile strength of tablets containing theophylline The aim of this thesis was to determine tensile strength of tablets containing theophylline. Tensile strength was studied as a function of the composition of mixtures of the used fillers and especially on their ratio. In the theoretical part, the used materials - lactose SpheroLac 100, microcrystalline cellulose Comprecel 102, dibasic calcium phosphate dihydrate Di-Cafos D160, anhydrous dibasic calcium phosphate Di-Cafos A150, theophylline and magnesium stearate are described. This work also evaluates force-displacement record, tensile strength and various factors that affect tensile strength. Parameters of force-displacement record and tensile strength of the tablets compressed with compresssion force 10 kN were evaluated in the experimental part. The measured results show that higher values of precompression energy (E1) and energy of plastic deformation (E2) were detected in mixtures A, C and E which contain Comprecel 102, and the lowest values were detected in mixtures B which contain Sphero-Lac 100 and Di-Cafos D160. Values of energy...
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Evaluation of disintegration time of tablets containing theophylline
Brtnová, Soňa ; Šklubalová, Zdeňka (advisor) ; Mužíková, Jitka (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Thesis supervisor: Doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Pavel Ondrejček Student: Soňa Brtnová Title of Thesis: Evaluation of disintegration time of tablets containing theophylline The influence of used fillers on energetic profile of compression, especially influence on disintegration time of tablets with theophylline as a model drug, was studied in this thesis. Four tablet fillers were studied - microcrystalline cellulose Comprecel 102, lactose SpheroLac 100, calcium hydrogen phosphate anhydrous Di- Cafos A150 and calcium hydrogen phosphate dihydrate Di-Cafos D160. Tablets contained different proportion of two fillers, theophylline as a model drug and lubricant magnesium stearate. Tablets were compressed by the same compaction force 10 kN. The force- displacement record was evaluated using the particular energies of compaction process. Parameters of compaction process were influenced mostly by Comprecel 102. According to results there is no possibility to replace Di-Cafos D160 with Di-Cafos A150 in the mixtures. It was also found that SpheroLac 100 and Di-Cafos D160 shows similar behavior. Time of disintegration of tablets is mostly dependent on the used fillers. Tablets...
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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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Influence of fillers and disintegrants type on properties of tablets with high dose drug.
Tranová, Thao ; Mužíková, Jitka (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Consultant: doc. PharmDr. Jitka Mužíková, Ph.D. Student: Thao Tranová Title of Thesis: Influence of fillers' and disintegrants' type on properties of tablets with high dose drug The work engages in the study of fillers' and extragranular superdisintegrants' influence on properties of tablets with high dose drug. Two types of granulate with lactose or microcrystalline cellulose were produced in high shear granulator. Eleven tablets groups with different type and amount of superdisintegrants were prepared from the granulates. Tablets contained 2 %, 3.7 %, 5.4 % of sodium croscarmellose or 2 % and 5.4 % of crospovidone. The tested parameters of tablets were friability, hardness, disintegration time and density. Accelerated stability studies lasting 6 months at temperature of 40 řC and relative humidity 75 % were done. The tablets were evaluated after 1.5, 3 and 6 months. All tablets had adequate friability, hardness, disintegration and density at T0. Increasing concentration of superdisintegrant decreased disintegration time. Tablets containing microcrystalline cellulose and sodium croscarmellose disintegrated faster than tablets containing lactose or crospovidone. Tablets with sodium croscarmellose had...
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Study of the influence of tablet mixture composition on the flow and consolidation properties
Ferechová, Daniela ; Šklubalová, Zdeňka (advisor) ; Macho, Oliver (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Supervisor: Pharmaceutical Technology doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Jana Brokešová Student: Daniela Ferechová Title of Thesis: Study of the influence of tablet mixture composition on the flow and consolidation properties Good flow properties of a tabletting mixture play an important role in the manufacturing of tablets. Flow behaviour of the commercial (original) tabletting mixture with poor flowability was evaluated in this thesis. The main aim was to find alternative fillers that may improve its flow. The granulometric characteristics and flowability of eight types of lactose and microcrystalline cellulose and their binary mixtures were studied. In comparison to the original tabletting mixture, the proposed modified one with both original fillers were replaced with new ones showed significantly better flow properties with steady state flow through the hopper orifice having a diameter of 10 mm. The results were confirmed using powder rheometer. The lower shear stress necessary to achieve flow under different normal loads as well as approximately 72 times lower cohesion value were detected for the modified tabletting mixture.
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Study of excipients' influence on the drug dissolution from tablets
Ouzký, Miroslav ; Šklubalová, Zdeňka (advisor) ; Mužíková, Jitka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Supervisor: Consultants: Assoc. Prof. PharmDr. Zdeňka Šklubalová, Ph.D. Mgr. Jana Brokešová, Mgr. Daniel Pěček Student: Miroslav Ouzký Title of Thesis: Study of excipientsʼ influence on the drug dissolution from tablets The aim of this work was to study the influence of excipients on the dissolution of the high-dose active substance from tablets. The tablets were compressed from the granules prepared by wet-granulation method. 11 batches of tablets which contained two different fillers: either lactose or microcrystalline cellulose, respectively; and extragranularly added disintegrant: either croscarmellose or crospovidone, respectively, in three concentration levels of 2 %, 3,7 % or 5,4 % were prepared. Tablets were packed into aluminium/PVC blisters. The paddle dissolution test was used to determine the release of the active substance into phospate buffer pH 7,2 at the time of preparation (time 0) and at the time points 1.5, 3 and 6 months of stability assay at 40 řC and 75 % relative air humidity. The results show that the drug release from tablets containing microcrystalline celulose was generally faster than from those containing lactose. The same was true for tablets to which croscarmellose was...
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Degassing of small amounts of aluminum alloy melt
Spáčil, Ivo ; Záděra, Antonín (referee) ; Kaňa, Václav (advisor)
The 40 kg melt was degassed by two methods: Immersion of a degassing tablet in a melt by an immersion bell and an argon degassing through a lance with a porous plug. Up-gassing tablets were also used during the experiment. The method of double weighing was used for evaluation. No technically significant degassing was achieved using degassing tablets. After degassing with tablets was observed a decrease in DI (Dichte Index) value with increasing residence time. Excessive dosing of the tablet does not ensure a higher degassing effect, it only ensures a higher turbulence of the reaction. Preheating the degassing tablets before use does not affect degassing. By preheating the up-gassing tablets, their reactivity is reduced. Two immersion bells with different proportions were tested. The bells do not ensure a homogeneous dispersion of bubbles in the melt. By argon degassing through the porous plug, the melt was degassed to a value DI = 1,87 %. The consumption of argon for degassing smaller amounts of melt is higher than for degassing larger amounts of melt. Argon refining is more efficient than using tablets.
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