|
|
Evaluation of viscoelastic parameters of co-processed materials and their components
Balušíková, Nikola ; 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: Nikola Balušíková Title of Thesis: Evaluation of viscoelastic parameters of co-processed materials and their components. Co-processed excipients (CPE) are defined as the combination of two or more substances, which are physically modified by an appropriate manufacturing process (e.g. wet granulation, spray-drying). These types of excipients are currently increasingly used for production of tablets by direct compression technology. Due to the availability of a wide range of initial materials for their production, there is a possibility to obtain large number of combinations with required characteristics and better properties than the simple physical mixtures. Although the composition of CPE may be very similar, the small changes in the component's characteristics can make them behave differently during compression. The thesis is focused on the evaluation of the viscoelastic properties of selected CPE and their components (Cellactose 80, Avicel CE 15, Avicel DG, Avicel HFE 102, MicroceLac 100, Arbocel A 300, Arbocel M 80, Avicel PH1 02, Guar gum, Mannitol, Di-Cafos D 160, Lactochem) using the stress relaxation test at maximal compression force of 5 kN...
|
|
|
Determination of the flowable liquid retention potential of silicates for polyethylene glycol 400 and propylene glycol
Jandáčková, Adriana ; Vraníková, Barbora (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: PharmDr. Barbora Vraníková, Ph.D. Student: Adriana Jandáčková Title of Thesis: Determination of the flowable liquid retention potential of silicates for polyethylene glycol 400 and propylene glycol Liquisolid systems are modern dosage form used to increase the bioavailability of poorly water-soluble drugs. The basic principle of liquisolid systems formulation lies in sorption of a drug in a liquid state onto a highly porous carrier which is subsequently coated with a material possessing a large surface area. This process leads to the forming of dry non- adhesive powder with properties suitable for further processing After oral administration, these systems allows elimination of dissolving as the drug is in already dissolved state. However, the ability of the powder to retain liquid while maintaining acceptable flow properties is limited. The aim of this diploma thesis was to determine the maximum amount of liquid (polyethylene glycol 400 and propylene glycol) that the powder (Veegum® HS, Veegum® F and Syloid® 244 FP) can absorb while maintaining suitable flow properties (flowable liquid retention potential). The value of flowable retention potential was established to 0.14 for Veegum® HS...
|
|
|
Compatibility study of excipients and active substance in tablet mixtures
Křikava, Jakub ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Mentor doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Daniel Pěček Student: Jakub Křikava Title of Thesis: Compatibility study of excipients and active substance in tablet mixture The aim of this work was to study interactions between lubricants and disintegrants used in the tablet mixtures for direct compression with high content of a drug. Binary mixtures of the drug and a selected excipient were prepared in the 1:1 ratio and that used in tablets. Modified tablet mixtures in which one of the excipients was excluded were prepared as well. The mixtures were subjected to the stress tests at the higher temperature/humidity. The influence on the thermal characteristics, porosity, the tensile strength and disintegration time of tablets was studied. Results showed that crospovidone interacts with a drug what worsened the properties of tablets and this negative effect was forced in the presence of stearic acid. Combination of crospovidone and stearic acid in tablet mixture increased the tablet tensile strength and disintegration time significantly. This combination cannot be recommended for the preparation of tablets. In case of the used drug, crosscarmellose sodium represents the better disintegrant.
|
|
|
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...
|
|
|
Effect of combination of mucoadhesive polymers on the behaviour of matrix tablets in the small intestine
Janoušek, Miroslav ; Vraníková, Barbora (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Mentor: PharmDr. Barbora Vraníková, Ph.D. Consultant: Mgr. Chiazor Ugo Ogadah Student: Miroslav Janoušek Title of Thesis: Effect of combination of mucoadhesive polymers on the behaviour of matrix tablets in the small intestine Colon-targeted drug delivery is highly desirable due to the direct treatment of local intestinal diseases, drug dose reduction, and minimization of systemic adverse effects. This effect can be achieved by several specific drug delivery systems based on different mechanisms. Generally, the most preferred are orally administrated formulations due to the relatively easy manufacturing and high adherence of patients to treatment. These include matrix systems based on mucoadhesive polymers that allow both targeting to the desired site (e.g. colon) and controlled drug release. For the above-mentioned reasons, the aim of the presented study was to evaluate the behavior of two mucoadhesive polymers, namely guar gum (GK), hypromellose K15M (HPMC K15M) and their combinations in biorelevant media simulating small intestine fluids (FaSSIF). The viscosity of the polymer dispersions was measured using a rotational rheometer. Polymer formulations (compacts) containing the model drug...
|
|
|
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...
|
guest ::
RSS feed.