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Compressibility of different batches of the drug Simvastatin.
Havelková, Adéla ; Řehula, Milan (advisor) ; Ondrejček, Pavel (referee)
This thesis deals with the characterization of pressing energy using the force-displacement diagram. The theoretical part defines the substance - simvastatin - and excipients which could occur in unknown samples. Also energies of pressing process, methods of assessment of force-displacement diagram for different substances and factors which affect pressability and thus the pressing energy are described there. The aim of the experimental part of the thesis was to characterize the energy profile using force-displacement diagram of eight batches of preparation simvastatin and to find applicable method of assessment. Tablets were pressed from each batch of preparations using a T1-FRO 50 machine at three pressing forces 5, 10, and 15 kN. Obtained parameters E2, E3, Elis and Pl were evaluated using three methods: method of outlying values, method of analysis of average for one factor and method of analysis of average for two factors. The most suitable method for assessment of divergent values is the method of analysis of average for two factors thanks to its complex character. This method showed lower values of the parameters E1, E2, Elis and Pl for batches E, G and H which could be caused by larger particles and higher moisture of granulate.
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The evaluation of flow properties of lactose.
Pazderková, Julie ; Šklubalová, Zdeňka (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Student: Julie Pazderková Title of Thesis: The evaluation of flow properties of lactose Lactose is one out of the traditional excipients used during the manufacturing of tablets. This diploma thesis describes flow properties of four commercially available grades of lactose, which differed in the preparation technique (milling, granulation). Three methods of bulk density evaluation and two methods of angle of repose determination were studied. It is recomended to form cone-like pile on the layer of material with regulation the distance between the hopper and the base. This process is better than forming the pile on teflon base. The relationship between bulk and consolidation behaviour of lactose and the geometric characteristics were studied. To describe the consolidation performance of materials, the expression of dependence of Hausner ratio on the number of taps can be recomended. A Brouckere mean diameter D[4,3] is suitable criterion for the studying of the correlation between the shape of particles and their flow. The use of Brouckere mean diameter should be investigated using other materials in future.
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Evaluation of the influence of filler sort and lubricant type and concentration on the parameters of the compaction equation
Ondrejček, Pavel ; Rabišková, Miloslava (advisor) ; Vetchý, David (referee) ; Bělohlav, Zdeněk (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Department of pharmaceutical technology Candidate Mgr. Pavel Ondrejček Supervisor prof. PharmDr. Miloslava Rabišková, CSc. Title of Doctoral Thesis Evaluation of the influence of filler sort and lubricant type and concentration on the parameters of the compaction equation This thesis is dealing with an evaluation of the compaction process of pharmaceutical excipients and their mixtures. The effect of the filler type, lubricant type and its concentration on the parameters of the compaction equation developed by Assoc. Prof. RNDr. Milan Řehula, CSc. is studied. Microcrystalline cellulose Avicel PH-200, lactose Lactochem Fine Crystals and calcium hydrogen phosphate dihydrate Emcompress were used as model fillers. These fillers of similar particle size were selected because of different bonding mechanism and varying course of the compaction process. Fillers were evaluated individually and then in their blends with lubricants magnesium stearate, sodium stearylfumarate and Syloid, i.e. modified colloidal silica in concentration 0,5 and 1 %. Moisture content and flow properties were determined in individual fillers. Particle size distribution, scanning electron microscope pictures and specific surface area measurements were...
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A study of the compaction process and the properties of tablets made of agglomerated and granulated lactose
Neprašová, Marie ; Mužíková, Jitka (advisor) ; Ondrejček, Pavel (referee)
The thesis studied tensile strength, disintegration time of tablets and energy profile of compression of agglomerated lactose Tablettose® 80 and of granulated lactose SuperTab® 30GR. Tested parameters were studied depending on compression force, addition of two concentrations of the lubricant magnesium stearate (0.5 and 1%) and 25% microcrystalline cellulose Microcel® MC-200. The tablets were compressed using the material testing machine T1 - FRO 50 TH.A1K Zwick/Roell. Used compression forces were 11, 13 and 15 kN, in the case of mixtures with Microcel® MC-200 11 kN. Tensile strength of tablets increased with compression force at both lactoses and it was higher in the case of mixtures with SuperTab® 30GR. Magnesium stearate decreased the tensile strength of tablets from Tablettose® 80 for all compression forces. Addition Microcel® MC-200 increased the tensile strength of tablets from both lactoses, more in the case of Tablettose® 80. Disintegration time of tablets increased with compression force. Higher concentrations of magnesium stearate in tablets increased disintegration time. Comparison of disintegration time of tablets from both lactoses depended on concentration of magnesium stearate. Addition of Microcel® MC-200 significantly shortened disintegration time of tablets in both lactoses. The...
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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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The evaluation of stress relaxation of lactose and calcium hydrogen phosphate mixtures intended for the preparation of tablets with theophylline.
Le, Thanh Tra ; Svačinová, Petra (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Mgr. Petra Svačinová, PhD. Student: Le Thanh Tra Title of Thesis: Evaluation of stress relaxation of mixtures of lactosum and calcii hydrogenphosphate for preparation tablets with theophylline This thesis studies viscoelastic behavior of fillers and tensile strength of tablets with theophylline. Used material are described in theoretical part: Laktosum SpheroLac 100, microcrystalline cellulose Comprecel 102, calcium hydrogenophosphate anhydrate Di-Cafos A150, calcium hydrogenophosphate dihydrate Di-Cafos D160, theophylline and magnesium stearate. Thesis also describes the stress relaxation test, methods of evaluation and it's application. Experimental part evaluates viscoelastic behavior and tensile strength through the test of stress relaxation with maximal compression force 10 kN and dwell time 180 s. The tensile strength of tablets is also evaluated. Experimental part evaluates parameters of elasticity Ai and plasticity Pi, which were obtained from the test of stress relaxation. It evaluates effect of different fillers on these parameters. The highest values were measured at mixtures E (Spherolac 100 a Comprecel 102), further at mixtures D (Spherolac 100 a Di-Cafos A150) and...
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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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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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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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A study of tableting materials and tablets with the combination of microcrystalline celulose and mannitol for orally disintegrating tablets.
Novotná, Andrea ; Mužíková, Jitka (advisor) ; Ondrejček, Pavel (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Pharmaceutical Technology Student: Andrea Novotná Consultant: PharmDr. Jitka Mužíková, Ph.D. Title of the Diploma Thesis: A study of tableting materials and tablets with the combination of microcrystalline cellulose and mannitol for orally disintegrating tablets This thesis compares co-processed dry binder Avicel® HFE-102 containing 90 % microcrystalline cellulose and 10 % mannitol with a physical mixture of related dry binders, microcrystalline cellulose (Avicel® PH-102) and mannitol (Pearlitol® 100SD) in the ratio of 9:1. Flow properties, compressibility, lubricant sensitivity, tensile strength and disintegration time of tablets are evaluated. Compressibility is evaluated by means of the energy profile of compression process, and lubricant sensitivity by means of the lubricant sensitivity ratio. The results are also compared with the microcrystalline cellulose for direct compression Avicel® PH-102 alone. The flow properties of the co-processed dry binder Avicel® HFE-102 alone and the physical mixture were comparable. Avicel® HFE-102 showed higher values of the energy of plastic deformation, tensile strength of tablets, and a markedly lower lubricant sensitivity than the physical mixture of dry binders. Tablets with the...
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