National Repository of Grey Literature 112 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Investigation of process parameters and their influence on spray dried particles properties
Grázová, Marcela ; Svačinová, Petra (advisor) ; Kováčik, Andrej (referee)
1. ABSTRACT Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Supervisor: PhamDr. Petra Svačinová, Ph.D. Consultant: Ing. Petr Koukal, Ph.D. Student: Marcela Grázová Title of Thesis: Investigation of process parameters and their influence on spray dried particles properties. The aim of the thesis was to determine to what extent it is possible to influence the particle size of the products by setting the parameters of the dryer. This particle size largely depends on the scale of the dryer used. Therefore, the aim was to determine whether a laboratory-scale spray dryer can either produce particles of variable size or particles of such size, that is typically obtained from production-scale devices. Particles prepared of meloxicam dispersions in hydroxypropylmethylcellulose phthalate were used for evaluation. A variety of input parameters for spray drying (drying gas inlet temperature, stock solution flow, concentration, and spray nozzle diameter) was used to prepare several batches of the product. The methodology Design of Experiments was used to identify the influence of individual input parameters on the product properties (particle size, glass transition temperature, and residual solvent content). Individual batches of the products were characterized by 1 H...
A study of the influence of co-processed dry binder type on the properties of oraly disintegrating tablets with the drugs ibuprofen and paracetamol.
Víšková, Michaela ; Mužíková, Jitka (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Mentor: Assoc. Prof. PharmDr. Jitka Mužíková, Ph.D. Consultant: Mgr. Thao Tranová Student: Michaela Víšková Title of Thesis: A study of the influence of co-processed dry binder type on the properties of orally disintegrating tablets with the drugs ibuprofen and paracetamol. This thesis deals with the study of orally disintegrating tablets containing co-processed dry binders Ludiflash® , Prosolv® ODT G2 and Parteck® ODT with analgesics ibuprofen and paracetamol. The tablets also include magnesium stearate as a lubricant and sucralose as a sweetener at a concentration of 1%. The energy profile of the compression process, tablet tensile strength, friability, porosity, wetting time, water absorption ratio and disintegration time of the tablets are evaluated. Tableting material with Prosolv® ODT G2 shows the lowest value of pre-compression energy, drugs increase it. Furthermore, it shows the highest value of compression energy that drugs reduce. Prosolv® ODT G2 and Parteck® ODT placebo tablets have higher tensile strength than Ludiflash® placebo tablets. Drugs reduce tablet tensile strength, paracetamol more significantly. Placebo tablets meet the requirement for friability (up to 1 %), whereas in the case...
Spray drying of drug suspension in lactose solution
Vlková, Klára ; Svačinová, Petra (advisor) ; Kováčik, Andrej (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Klára Vlková Title of Thesis: Spray drying of a drug suspension in lactose solution Spray drying can be used to increase the solubility and thus bioavailability of drugs that are poorly soluble in water. In the present work, particles from a suspension of meloxicam in lactose solution were prepared by spray drying. The effect of the nozzle size of 0.7 mm and 1.4 mm, the effect of drug concentration of 0.5 g/100 ml and 1 g/100 ml, and the effect of lactose concentration on the properties of the resulting particles were investigated. The lactose solutions used had concentrations of 15, 20 and 25 %. The appearance and size of the formed particles were evaluated using optical and scanning electron microscopy (SEM). The amount of drug released was investigated using dissolution and the thermal characteristics of the particles were evaluated using differential scanning calorimetry (DSC). The evaluation by SEM and DSC was then performed again 6 months after the first measurement. The resulting particles were spherical in shape with no surface irregularities. Some of them contained clusters of meloxicam particles. At the second observation after 6 months,...
Polymeric particles for targeted and enhanced bioavailability
Kozáčková, Daniela ; Holas, Ondřej (advisor) ; Svačinová, Petra (referee)
7 ABSTRACT Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Mentor: PharmDr. Ondřej Holas, Ph.D. Consultant: Mgr. Barbora Boltnarová Student: Daniela Kozáčková Title of thesis: Polymeric particles for targeted and enhanced bioavailability Nanoparticles prepared from biodegradable and biocompatible polymers are useful for targeted therapy of inflammatory diseases and increase the bioavailability of poorly water-soluble anti-inflammatory drugs. Targeted distribution is mainly mediated by the physico-chemical properties of nanoparticles. This can reduce unwanted side effects of encapsulated drug. The ideal properties of nanoparticles for passive targeting to cells of the mononuclear phagocytic system (MPS) are size in the range of 100 nm to 300 nm, hydrophobic character and negative surface charge. Matrix-type polymeric nanoparticles were prepared. Prepared nanoparticles were evaluated for size, polydispersity index, zetapotential and encapsulation efficiency of the drug. Three anti-inflammatory substances with different water solubility - a dexamethasone, a dexamethasone acetate and a curcumin were encapsulated. The matrix of nanoparticles was made of PLGA copolymer, three types of PLGA with different lactide:glycolide ratio were used. Nanoparticles...
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...
Preparation of spray-dried powder containing active substance, chitosan and surfactant
Kubová, Helena ; Svačinová, Petra (advisor) ; Smékalová, Monika (referee)
7 2 ABSTRACT Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Helena Kubová Title of Thesis: Preparation of spray-dried powder containing active substance, chitosan and surfaktant The main of this work was to prepare spray-dried powder containing meloxicam, chitosan and CTAB as surfactant. Spray drying is a method used to increase the bioavailability of poorly soluble drugs. Surfactants are substances that increase the solubility of drugs by the mechanism of micellar solubilization. Samples with different concentrations of meloxicam and constant amount of CTAB and chitosan used as a carrier were prepared. Three different temperatures, 170 řC, 190 řC and 210 řC were used for spray drying. The effectiveness of CTAB on properties of prepared particles and on the drug release from the samples was evaluated. The 1,4 mm diameter nozzle was used for spray drying. Optical microscopy and SEM were used to evaluate the appearance of prepared particles and the thermal characteristics were evaluated by DSC. The amount of drug released was evaluated using dissolution test. The particles of obtained powder had an irregular plate-like shape corresponding to chitosan particles. Spherical particles of meloxicam with CTAB...
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...
Fractal aspects of flow and consolidation behaviour of microcrystalline cellulose.
Šofranková, Alexandra ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
7 2 Abstract Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Consultant: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Student: Alexandra Šofranková Title of Thesis: Fractal aspects of flow and consolidation behaviour of microcrystalline cellulose The object of this diploma thesis was to study the flow and consolidation characteristics of three types of microcrystalline cellulose. The granulometric characteristics, including the linear fractal dimension, were estimated using the optical microscopy. The bulk and tapped density, the angle of repose and the flow rate through an orifice of the hopper were evaluated. True density of the materials and the porosity of a loose powder bed were determined by helium pyknometry. The changes of density by the gravity consolidation were studied; the relationship of Hausner ratio on the number of taps describes best the differences in the consolidation behaviour of the substances. Modelling the consolidation kinetic by the exponential law allowed to determine the parameter N1/2, which shows the number of taps needed to reach one half of the powder volume reduction. The values of N1/2 within a range of 6,9-18 correlated well with the particle size of the used types of microcrystalline cellulose.
Study of monolayer lipid models of skin barrier diseases
Doláková, Andrea ; Švecová, Barbora (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Author: Andrea Doláková Supervisor: PharmDr. Barbora Školová, Ph.D. Title of thesis: Study of lipid monolayer models of skin barrier diseases Skin protects human body from external factors and maintain internal integrity of organism. Skin barrier is formed by corneocytes and lipid matrix in intercellular space of stratum corneum, the uppermost layer of epidermis. Lipid matrix consists of ceramides, free fatty acids and cholesterol. The composition and organisation of lipid matrix are essential for the skin barrier properties. Ceramides are synthetized from glucosylated ceramide and sphingomyelin by hydrolitic enzymes β-glucocerebrosidase and sphingomyelinase. Insufficiency or malfunction of these enzymes lead to functionless skin barrier. The aim of this work was to prepare and study monolayer lipid models, which simulated the malfunction of sphingomyelinase in skin diseases. For valuation we used several techniques such as Langmuir monolayers, Brewster angle microscopy (at the air-liquid interface), Langmuir-Blodgett technique and atomic force microscopy. Monolayers with 100% substitution of sphingomyelin layout the most readily with rising surface pressure and the course of their isotherm is very...
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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