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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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Determination of the compressibility of ascorbic acid using stress relaxation test and force-displacement record
Ledvinová, Ivana ; 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: Ivana Ledvinová Title of Thesis: Determination of the compressibility of ascorbic acid using stress relaxation test and force-displacement rekord This thesis deals with the determination of compressibility of ascorbic acid. Test force-displacement record and stress relaxation test were used for a description of the compression process. Viscoelastic properties of ascorbic acid are evaluated based on parameters obtained from these two methods. Stability of ascorbic acid during compression process was also evaluated. The method of differential scanning calorimetry (DSC) was used for this evaluation. The tablets for force-displacement record were compressed by maximal compression forces of 5, 10, 15, 20, 25, 30, 35, and 40 kN. For the stress relaxation test were compression forces of 5, 10 and 15 kN. The tablets compressed using force-displacement record were used as samples for DSC method. The purpose of the measurement was to determine possible changes in the structure of ascorbic acid caused by different compression forces. From the obtained values can be concluded that structural changes or decomposition of ascorbic acid does not...
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A study of the influence of lubricants on the ejection force of the tablets.
Novotná, Nikola ; Mužíková, Jitka (advisor) ; Ondrejček, Pavel (referee)
The aim of this study was to evaluate the effect of the type of lubricant, its concentration and mixing time with granules on the tablet hardness, ejection force and the lubrication index. Lactose was used as a filler in granules and polyvinylpyrolidone as a binder. Granules were prepared by wet granulation. Three types of talc were used in concentrations 1%, 3%, 5%, 7% a 10% and magnesium stearate in concetrations 1%, 2% a 3% as lubricants. Tablets were produced by tablet press DOTT Bonapace (model CPR-6) with the possibility to measure the force of the upper and lower punch and force-displacement. These values were used for the calculation of the lubrication index. The values of lubrication index were used for the lubricants comparison. The lubrication index with magnesium stearate did not change either with increasing concentration or with mixing time with granules. In case of each type of talc, the lubrication effect rose with increasing concentration but time of the mixing did not have any significant effect on the lubrication potential. Tablet strength decreased with higher lubricant concentration and longer mixing time when magnesium stearate was used. With increasing concentration of the lubricant tablet strength with talc first increased then stagnated or started to decrease. The higher...
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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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Determination of optimal compression force and speed of compression for the production aciclovir tablets
Vlachová, Hana ; Řehula, Milan (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Student: Vlachová Hana Consultant: Doc. RNDr. Milan Řehula, CSc. Determination of optimal compression forces and speed of compression for the production of aciclovir tablets. This thesis deals with the characterisation of impact compression process on hardness of the tablets. The theoretical part of the thesis describes the effective substance - aciclovir. It also describes compression equations which explain process of compression and factors influencing terminal weight and hardness of tablets. The aim of the experimental part of the work is to measure physical properties of the tablets and find compression forces and speed of compression which are suitable for compression tablets. Tablets were pressed using Kilian Synthesis 700 machine at six compression forces in the range from 4 kN to 14 kN. The height, weight and hardness of each tablet were measured immediately after dressing and note to help for later calculation. The result of the study was to determine the impact of compression forces and compression speed on tablet hardness and weight. Tablet weight decreses with increasing comppession forces. Hardness increases with increasing compression forces. The range of radial hardness...
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Evaluation of compressibility of paracetamol
Šorf, Aleš ; Řehula, Milan (advisor) ; Ondrejček, Pavel (referee)
The objective of this work was to evaluate the compressibility of paracetamol by determination of compression and viscoelastic properties of the active substance and also to detect eventual changes in crystal modification of the substance during the compression process. The parameters of the compression equation were determined using tree-exponential equation developed at the Department of pharmaceutical technology. Mutual interactions between particles were also studied by stress relaxation test using compression forces 5, 10 and 15 kN, as well as energetic parameters of a force-distance record using compression forces from 5 to 40 kN. Tablets made in the last mentioned test were used as samples for DSC analysis to seek potential changes in the crystal structure of paracetamol when undergoing the compression process. The evaluation of the executed tests suggested that compression ability of paracetamol in basic form I is very poor and its plasticity when being compressed by commonly used pressures is about 50%, which is considered as very low. It was also found out that any crystal structure changes of the active substance did not occur during compression.
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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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A study of the compressibility of direcly compressible tableting materials with tramadol hydrochloride.
Kubíčková, Alena ; Mužíková, Jitka (advisor) ; Ondrejček, Pavel (referee)
This thesis evaluates and compares compressibility of directly compressible tableting materials for the preparation of hydrophilic gel matrix tablets containing tramadol hydrochloride. Prosolv® SMCC 90 and Disintequik™ MCC 25 were used as the dry binders. Hypromelloses Methocel™ Premium K4M and Methocel™ Premium K100M were used in concentrations of 30 % and 50 %. Magnesium stearate was used as the lubricant in concentration of 1%. The compressibility was evaluated by means of the energy profile of the compression process and determination of tensile strength of the tablets. The tableting materials with Prosolv® SMCC 90 exhibited the higher values of the total energy of compression than those with Disintequik™ MCC 25 at the same compression forces, tramadol decreased these values slightly. The tableting materials with Disintequik™ MCC 25 exhibited higher values of the total energy of compression in 50% concentration of both Methocels™ . In the case of Prosolv® SMCC 90 the values of plasticity were higher than at tableting materials with Disintequik™ MCC 25, particularly in 30% concentration of both types of Methocel™ . Tramadol decreased the plasticity slightly. The tableting materials with Prosolv® SMCC 90 provided stronger tablets. Tramadol decreased the strength of tablets and the strength values...
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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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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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