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Development of a new model for the evaluation of compression phase of compaction process
Grande, Vojtěch ; Ondrejček, Pavel (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of Pharmaceutical Technology Consultant: PharmDr. Pavel Ondrejček, Ph.D. Student: Mgr. Vojtěch Grande Title of thesis: Development of a new model for the evaluation of compression phase of compaction process By evaluating the compression process during the preparation of tablets, we can find out information about the pressed material. This information is useful for the materials and tableting mixtures comparison, but also for predicting of potential problems during manufacturing. The theoretical part of this thesis is focused on the description of the methods most commonly used for the evaluation of pharmaceutical substances. Furthermore, there is a derivation of a new mathematical model for the evaluation of the compression phase of the compaction process and the corresponding script for the mathematical-statistical program QCExpert. In the experimental part of the thesis, this new proposed model is used for the evaluation of two known and frequently used fillers. Lactose and microcrystalline cellulose are used as model fillers. These are compressed separately and in a mixture. The results of this evaluation are compared with the force-displacement record and the stress relaxation. The results of the work showed that the new...
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Preparation of spray-dried powder containing different amount of chitosan
Pětioká, Michaela ; Svačinová, Petra (advisor) ; Ondrejček, Pavel (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Supervisor: PharmDr. Petra Svačinová, Ph.D. Consultant: PharmDr. Tereza Vařilová Student: Michaela Pětioká Title of Thesis: Preparation of spray-dried powder containing different amount of chitosan The aim of the thesis is the preparation of spray-dried particles, evaluation of their properties and assessment of the influence of different amounts of chitosan on the evaluated properties. The particles were prepared from a suspension of chitosan in meloxicam solution with the addition of sodium lauryl sulfate as a surfactant. The suspensions contained different amounts of chitosan (12.5; 10; 7.5 or 5 g) and meloxicam (62.5; 50 or 37.5 mg), the amount of sodium lauryl sulfate was uniform for all suspensions (7.5 g). All suspensions were dried at 190 řC. Optical microscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and dissolution tests with spectrophotometric evaluation were used to evaluate the properties of the dried samples and their particles. The prepared particles had an irregular spherical shape and occurred independently and in clusters. Some of the particles were hollow and there were smaller particles inside their cavities. The shape and structure of the dried...
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The influence of the die size on the compaction process
Marcinková, Nikola ; Ondrejček, Pavel (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Department of Pharmaceutical Technology Consultant: Mgr. Pavel Ondrejček, Ph.D. Student: Nikola Marcinková Title of Thesis: The influence of the die size on the compaction process This diploma thesis is focused on exploration the influence of the die size on the compaction process. That was evaluated by parameters of three-exponential equation. Compressibility was studied by using force-displacement record. In this work was also observed an effect of die size on the tensile strength. In processing the experimental part of this work were used four different model materials. Microcrystalline cellulose and dicalcium phosphate are used as model fillers and theophylline and paracetamol as model active substances. Compaction of these materials was carried out in dies of size 7 mm, 9 mm, 11 mm, 13 mm and 15 mm. The results of the work showed that the die size significantly affects all parameters force-displacement record. With the growing size of the die there was a reduction of energy parameters. Most of the compaction parameters were statistically influenced. Increasing die size caused reducing volume reduction and energy consumption and increased speed of volume reduction at the stage of pre- compression and elastic...
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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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Determining the compression behaviour of celluloses.
Ondrejček, Pavel ; Řehula, Milan (advisor) ; Špaček, Vladimír (referee)
Mechanical resistance of tablets is usually described by crushing force, or by tensile strength. Method used in this thesis records crushing force and path of crushing. This force-path record can be used to calculate crushing energy. Crushing force, crushing path and crushing energy can be used to calculate other parameters that characterize tablet properties. This thesis uses crushing force, volume crushing force, tensile strength, crushing energy, volume crushing energy and crushing energy related to tablet weight to describe tablets compressed of powdered cellulose, microcrystalline cellulose, hydroxypropylcellulose and lactose monohydrate. Results of this thesis shows descent of tensile strength in this order: microcrystalline cellulose Avicel PH-112, microcrystalline cellulose Avicel PH-101, hydroxypropylcellulose, powdered cellulose and lactose monohydrate. Kinetic characteristics of tablets descent in this order: hydroxypropylcellulose, microcrystalline cellulose Avicel PH-101, microcrystalline cellulose Avicel PH-112, powdered cellulose and lactose monohydrate.
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A study of the compressibility and properties of tablets from co-processed dry binder composed of microcrystalline cellulose and glyceryl monostearate.
Muchová, Sandra ; Mužíková, Jitka (advisor) ; Ondrejček, Pavel (referee)
The paper studies the co-processed dry binder LubriTose™ MCC from the viewpoint of energy evaluation of the compression process, strength and disintegration time of tablets. The results were compared with the identical evaluation of physical mixtures of microcrystalline cellulose with several types of lubricants. LubriTose™ MCC showed the lowest value of energy for friction, the highest value of energy accumulated by the tablet, and the highest plasticity of all tableting materials under study. There were no marked differences in the values of the energy of decompression. The tensile strength of tablets from LubriTose™ MCC was lower than in those from the mixture of Vivapur® 12 and glycerol monostearate, in the compression forces of 4 and 5 kN it was comparable with the tensile strength of tablets from Vivapur® 12 with poloxamer 407. Disintegration time of tablets from LubriTose™ MCC was shorter than that of those from Vivapur® 12 with glycerol monostearate at the compression force of 3 kN, in the case of the compression forces of 4 and 5 kN no statistically significant difference was found between the values of these tableting materials.
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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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Properties and the employment of parenteral preprations.
Kotásková, Denisa ; Šklubalová, Zdeňka (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Consultant: Doc. PharmDr. Šklubalová Zdeňka, Ph.D. Student: Denisa Kotásková Title of Thesis: Properties and the employment of parenteral preparations. This thesis presents parenteral preparations. The aim of thesis was introduction of injection and infusion preparations, which are the most commonly used parenteral drug forms. The emphasis is placed on the complete list of excipients which are essential ingredients because they ensure the safety and efficacy of this formulation and positively influence its properties. The essential pharmacopoeial quality requirements are shortly discussed, such as sterility, non-pyrogenity, the absence of particulate matter, nominal volume or airtight containers. The largest part of the thesis is focused on the use of the parenteral infusion. It deals primarily with the use of electrolyte solutions in the treatment of disorders of the inner body balance. The important chapter is the parenteral nutrition, which includes the most important nutrients such as carbohydrates, amino acids and microheterogenous oil emulsions. The peritoneal dialysis solution and the plasmaexpander solution are the supplement of this thesis. The thesis also attends to the production...
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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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