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The effect of the drying temperature on the properties of spray-dried lactose
Slezáčková, Jana ; Svačinová, Petra (advisor) ; Vraníková, Barbora (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Jana Slezáčková Title of Thesis: The effect of the drying temperature on the properties of spray-dried lactose The aim of this work was to investigate the effect of inlet temperature on the physicochemical properties of spray dried lactose. 10% lactose solution was prepared by dissolving D-lactose monohydrate in distilled water and subsequently dried in a laboratory-scale spray drier. The inlet temperature of 130 řC - 200 řC was used. The physicochemical properties of lactose particles was investigated by optical microscopy and differential scanning calorimetry. Results indicated the influence of inlet temperature on particle size and shape and thermal properties of dried material. The morphology of spray-dried lactose showed tendency to higher sphericity when higher temperatures in a spray-drying process were used. Most of particles was in range 2,5 - 7,5 μm. The particles larger than 20 μm wasn't observed at the inlet temperature of 150 - 200 řC. At the inlet temperature over 150 řC the glass transition temperature was noticed. The glass transition temperature was observed around 24,8 - 63,5 řC. It was evident that higher drying temperature...
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The influence of the tableting speed on the parameters of the stress relaxation test
Borkovcová, Renáta ; Svačinová, Petra (advisor) ; Ondrejček, Pavel (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Renáta Borkovcová Title of Thesis: The influence of the tableting speed on the parameters of the stress relaxation test This diploma thesis evaluates the influence of tableting speed on the viscoelasticity parameters of stress relaxation test and tensile strength of tablets. Microcrystalline cellulose Avicel® PH-200, lactose monohydrate SpheroLac® 100, calcium hydrogen phosphate dihydrate Di-Cafos® D 160 and potato starch were used as model excipients and magnesium stearate was used as lubricant. The theoretical part is devoted to informations about tablets as a dosage form and description of excipients, which where used in experimental part. Subsequently, plasticity and elasticity of material were characterized and methods of their evaluation were described. The stress relaxation test and its evaluation using the three exponential equation were characterized in more detail. The following chapters describe the influence of tableting speed and lubricants on tensile strength of tablets. The experimental part deals with viscoelastic properties of individual materials and their mixtures with lubricant at concentration of 1 %. This properties were...
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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.
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The evaluation of viscoelastic properties of two types of pregelatinized corn starch using stress relaxation test
Hájková, Jana ; Svačinová, Petra (advisor) ; Mužíková, Jitka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: PharmDr. Petra Svačinová, Ph.D. Student: Jana Hájková Title of Thesis: The evaluation of viscoelastic properties of two types of pregelatinized corn starch using stress relaxation test This thesis deals with viscoelastic properties of two partially pregelatinized starches (Starch 1500® and Lycatab® C) and with the evaluation of the tensile strength of tablets. In the theoretical part are described characterisations of used starches, lubricants and their effect on compression of starches. There is also described compression process and its evaluation with stress relaxation test. Experimental part of this thesis is focused on tablet compression and evaluation of their viscoelastic properties and tensile strength of tablets. For evaluation of viscoelasticity was used stress relaxation test. Tablets were compressed at compression forces of 13, 15 and 17 kN. Magnesium stearate and stearylfumarate in 0,5 % and 1,0 % concentrations were used as lubricants. The differences in parameters of elasticity (A1-3) and plasticity (P1-3) between both types of partially pregelatinized maize starches, effect of lubricants and different compression forces were observed. In all three phases of compression...
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The influence of the dwell time on the parameters of the stress relaxation test for microcrystalline cellulose and starch.
Hamplová, Kateřina ; Svačinová, Petra (advisor) ; Vraníková, Barbora (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Mgr. Svačinová Petra, Ph.D. Student: Hamplová Kateřina Title of Thesis: The influence of the dwell time on the parameters of the stress relaxation test for microcrystalline cellulose and starch. This thesis is focused on the viscoelastic properties of pharmaceutical excipients and the tensile strength of tablets. The theoretical part describes used materials. Microcrystalline cellulose and starch were used as fillers and magnesium stearate at concentration of 1% was used as lubricant. The stress relaxation test and its evaluation and utilization not only in pharmacy is described as well as the tensile strength of tablets. The experimental part deals with the viscoelastic properties of used materials and their mixtures with lubricant. These properties were evaluated using the stress relaxation test. At maximum compression force of 10 kN the length of dwell time was changed (60 s, 120 s, 180 s, 240 s, 300 s, 360 s, 420 s, 480 s, 540 s, 600 s). For derived parameters of elasticity A1-3 and plasticity P1-3 the dependence on the length of dwell time was evaluated. Parameter A1 increases with increasing dwell time for all substances. For parameters A2, A3, the dependence on the dwell...
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The influence of the dwell time on the parameters of the stress relaxation test for lactose and calcium hydrogen phosphate.
Straková, Markéta ; Svačinová, Petra (advisor) ; Holas, Ondřej (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Mgr. Petra Svačinová, Ph.D. Student: Straková Markéta Title of Thesis: The influence of dwell time on the parameters of the stress relaxation test for lactose and calcium hydrogen phosphate The aim of this thesis is to find out viscoelastic properties of pharmaceutical excipients and to evaluate the tensile strength of tablets made of them. The theoretical part describes used materials, these are lactose, calcium hydrogen phosphate and magnesium stearate. The thesis also deals with the stress relaxation test, its evaluation and usage. Tensile strength, calculation and various factors that affect tensile strength are described in the text. The experimental part deals with viscoelastic properties of used materials and their mixtures with lubricant using the stress relaxation test. Different dwell times (60 s, 120 s, 180 s, 240 s, 300 s, 360 s, 420 s, 480 s, 540 s, 600 s) were used for individual measurements. The relation between elasticity parameters (A1, A2, A3) and plasticity parameters (P1, P2, P3) depending on the dwell time was investigated. As for calcium hydrogen phosphate, the dwell time 180 - 240 seconds was found as the most appropriate. As for lactose, the optimum dwell...
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Influence of lubricants on viscoelastic parameters of compaction process
Svačinová, Petra ; Rabišková, Miloslava (advisor) ; Kubová, Kateřina (referee) ; Zámostný, Petr (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department Pharmaceutical technology Candidate Mgr. Petra Svačinová Supervisor Prof. PharmDr. Miloslava Rabišková, CSc. Title of Doctoral Thesis Influence of lubricants on viscoelastic parameters of compaction process This thesis deals with an evaluation of lubricant's influence on viscoelastic parameters of compaction process. The force-displacement record and stress relaxation test were used for this evaluation. This study evaluates the viscoelastic parameters on three fillers intended for direct compression, i.e. microcrystalline cellulose Avicel PH-200, lactose Lactochem Fine Crystals and calcium hydrogen phosphate dihydrate Emcompress. Magnesium stearate and modified colloidal silica Syloid were used as lubricants at concentrations of 0.5 % and 1 %. Particle size and shape and specific surface area were determined for all used excipients. Flow properties were studied for individual fillers and also for their mixtures with lubricants. Subsequently, tablets were compressed from fillers and mixtures using force-displacement record and stress relaxation test, and viscoelastic parameters were evaluated. The applied compression forces for both methods were 5 kN, 10 kN and 15 kN. The hardness of tablets was measured. The results show...
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A comparison of viscoelastic properties of mixtures of lactose and different lubricants using the stress relaxation test.
Přeučilová, Michaela ; Svačinová, Petra (advisor) ; Jirásková, Johana (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Mgr. Petra Svačinová, Ph.D. Student: Michaela Přeučilová Title of Thesis: A comparison of viscoelastic properties of mixtures of lactose and different lubricants using the stress relaxation test This diploma thesis deals with viscoelastic properties of pharmaceutical excipients and tensile strength of tablets made of these excipients. Theoretical part is dedicated to description of lactose and lubricants, further the tablets compressibility and compression energy profile are described. The end of theoretical part deals with the stress relaxation test, with evaluation methods and the stress relaxation test influence on lactose tablets with different types of lubricants as well. The experimental part deals with the evaluation of the viscoelastic properties of two types of lactose and their mixtures with different types of lubricants at concentration of 1%. These characteristics were evaluated by stress relaxation test. All tablets were compressed by compression forces of 13 kN and 15 kN with dwell time 180 seconds. The study was about differences between two types of lactose, effect of lubricants and effect of two different compression forces on parameters of elasticity A1 -A3 and...
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Fractal aspects of sodium chloride flow.
Dvořáčková, Simona ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: Assoc. Prof. PharmDr. Zdeňka Šklubalová, PhD. Student: Simona Dvořáčková Title of Thesis: Fractal aspects of sodium chloride flow The flowability of substances is affected by their granulometric characteristics, such as the size and the shape. In this thesis, the relations between particle size and flow rate of the sodium chloride size fractions in a range of 80-630 µm through the circular outlet of the conical stainless hopper in a range of 6-15 mm are studied. The Jones & Pilpel power equation was used to model the dependence. A linear relationship between the exponent of the Jones & Pilpel power equation and the mean size of particles was noted. The fractal aspects of flow rate (the mass and/or the volume ones) were investigated using the results of the optical microscopy. A nonlinear dependence between the flow rate and the mean particle size and/or the particle perimeter was detected.
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A study of the compressibility and the lubricant sensitivity of two types of pregelatinized corn starch.
Hadravová, Nikola ; Mužíková, Jitka (advisor) ; Svačinová, Petra (referee)
This thesis is comparing two types of partially pregelatinized corn starch, Starch 1500® and Lycatab® C from the standpoint of compressibility and lubricant sensitivity of these substances. Magnesium stearate and sodium stearyl fumarate in 0.5 and 1 % concentration were used as lubricants. Starches were also tested in the mixtures with spray- dried lactose Flowlac® 90 in 10, 20 and 30 % concentration. The compressibility was evaluated by means of energy profile of compression process and determination of tensile strength of tablets. Lubricant sensitivity of substances was evaluated using LSR values. The tableting materials with Lycatab® C exhibited higher values of the total compression and pre-compression energy, than with Starch 1500® tableting materials, lubricants addition decreased these values. The tableting materials with Flowlac® 90 exhibited higher values of these energies for both types of starch and lubricants addition decreased their values. Higher values of compression energy were in tableting materials with Lycatab® C, also decreased by lubricants. Flowlac® 90 addition had no effect in compression energy with Starch 1500® , value decreasing was with Lycatab® C substance. The tableting materials with Lycatab® C had higher value of plasticity than with Starch 1500® , lubricants...
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