|
|
Study of influence of hydrophilic carriers on the solubility of a poorly soluble drug
Veselá, Eliška ; Šklubalová, Zdeňka (advisor) ; Vraníková, Barbora (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Department of Pharmaceutical Technology Supervisor: Doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Jana Brokešová Student: Eliška Veselá Title of Thesis: Study of influence of hydrophilic carriers on the solubility of a poorly soluble drug The aim of this thesis was to enhance the solubility of a poorly soluble model drug meloxicam (MLX) by preparing binary interactive mixtures with hydrophilic carriers by simple mixing and co-milling. The mixtures were characterized for granulometric properties. The dissolution studies were carried out using the USP-4 apparatus assembled with a flow-through powder cell in an open-loop system. The dissolution rate rrel (min-1 ) and the amount of released drug mrel (%) were evaluated. The observable positive effect of carriers was registerred in terms of increasing the dissolution rate and the amount of released drug for both mixed and co-milled mixtures comparing to the raw drug. Mixtures with hypromellose were the exception; the improvement of the monitored parameters was not detected.
|
|
|
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.
|
|
|
Study of influence of hydrophilic carriers on the solubility of a poorly soluble drug
Veselá, Eliška ; Šklubalová, Zdeňka (advisor) ; Vraníková, Barbora (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Department of Pharmaceutical Technology Supervisor: Doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Jana Brokešová Student: Eliška Veselá Title of Thesis: Study of influence of hydrophilic carriers on the solubility of a poorly soluble drug The aim of this thesis was to enhance the solubility of a poorly soluble model drug meloxicam (MLX) by preparing binary interactive mixtures with hydrophilic carriers by simple mixing and co-milling. The mixtures were characterized for granulometric properties. The dissolution studies were carried out using the USP-4 apparatus assembled with a flow-through powder cell in an open-loop system. The dissolution rate rrel (min-1 ) and the amount of released drug mrel (%) were evaluated. The observable positive effect of carriers was registerred in terms of increasing the dissolution rate and the amount of released drug for both mixed and co-milled mixtures comparing to the raw drug. Mixtures with hypromellose were the exception; the improvement of the monitored parameters was not detected.
|
|
|
Bioactive substances for face cream: Determination of stability of face cream incorporated with goat's milk
Dostálová, Tereza ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
The aim of this bachelor thesis is a stability trial of a skin cream incorporated with goat milk lyophilizates prepared in usual laboratory conditions. Firstly, the goat milk was denatured, to be further analysed via FTIR, elemental analysis and thermogravimetry. To compare the denaturation effect, measurements with native goat milk sample were performed as well. Next, an emulsion was prepared. First stability tests were performed using analytical centrifuge and the cream preparation procedure and component ratio was optimized. Stability trials were carried out at specified time intervals. Rheological properties – especially yield stress values and structure strength, determined by linear viscoelastic region and complex modulus – thermal endurance measured via differential scanning calorimetry and visual validation via optical microscopy and sample observation were tested and performed. Skin cream stability of sample stored at laboratory temperature was demonstrated, showing moderate sings of structure destabilisation. Product suitability for dry skin was proved by sensory analysis. The skin feeling was pleasant, and the cream moisturized the surface area, that it was applied to, according to evaluators. Visually, the emulsion appeared to maintain its properties during the experiment time range, it did not undergo a complete degradation of separation into two original phases, nor it was degraded, for example by mold.
|
|
|
Phase transformation in magnesium MgZnAl-based alloys
Kodetová, Veronika ; Vlach, Martin (advisor) ; Mathis, Kristián (referee)
In the present work, there was analyzed thermal evolution of the phase transformation in the MgZnAl and MgZnAlCa alloys with different concentration of the Zn and Ca. The grains were occupied by the phase with quasicrystaline icosaedral structure in the as-cast alloys and after isochronal annealing up to 240 řC. The thermal measurements revealed two exothermic effects in the MgZnAl alloy and three exothermic effects in the MgZnAlCa alloy during linear heat treatment in the temperature range of 100 - 250 řC. In agreement to the thermal response, two and three stages of electrical resistivity decrease were observed in the same temperature range. The lower thermal changes, absolute resistivity changes and microhardness were observed in the alloy with Ca-addition and lower concentration of Zn.
|
|
|
The release of terbinafine from polyesters branched with polyacrylic acid
Jakubíková, Hana ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Name of the student: Mgr. Hana Jakubíková Title of thesis: The release of terbinafine from polyesters branched with polyacrylic acid Consultant: PharmDr. Eva Šnejdrová, Ph.D. In this rigorous thesis, thermal and release properties of solid dispersions with terbinafine based on polyesters of lactic and glycol acid, branched with different concentration of polyacrylic acid, are studied and presented. Theoretical part summarizes current knowledge about terbinafine and its ways of application, advantages and disadvantages of solid dispersions and selection of a suitable polymeric carrier. In the experiment, solid dispersions were prepared by melting method, or solvent method using methyl-formate. The swelling rate and erosion rate were determined. The active pharmaceutical ingredient was incorporated into the polymer in form of hydrochloric salt or free base form in concentration of 10 %. Dissolution tests of terbinafine at 37 řC and pH 7.4 (phosphate buffer) were performed. Terbinafine concentration was determined spectrofotometrically at wavelength of 223 nm. Thermal analyses of solid dispersions revealed molecularly dispersed drug in concentration of 10 %. Polyesters degradation was running at pH 7,4 for...
|
|
|
Phase transformation in bio-compatible Mg-based alloys
Hornát, Bohumil ; Vlach, Martin (advisor) ; Mathis, Kristián (referee)
ÙÖÖ ÒØ Ñ Ø Ö Ð Ö × Ö × Ó Ò Ò ÑÔÖÓÚ Ò Ú ÓÖ Ó Ð ØÛ Ø Ñ ¹ Ò × ÙÑ ÐÐÓÝ Û Ú Û Ù× ×Ô ÐÐÝ Ò ØÖ Ò×ÔÓÖØ Ò Ù×ØÖÝ Ò Ñ ¹ Ò ž Å ¹Ê ¹Ë ¹ÅÒ × ÐÐÓÝ× Ò ÓÒ× Ö × ÔÖÓÑ × Ò Ñ Ø Ö Ð ÓÖ Ø × ÔÔÐ Ø ÓÒמ ÁÒ Ø ÔÖ × ÒØ ÛÓÖ ¸ Ø Ö Û × ×ØÙ Ø ÖÑ Ð ÚÓÐÙØ ÓÒ Ó Ø Ô × ØÖ Ò× ÓÖÑ Ø ÓÒ× Ò Å ¹Ê ¹Ë ¹ÅÒ × ÐÐÓÝ× Ý Ö ÒØ Ð × ÒÒ Ò ÐÓ¹ Ö Ñ ØÖÝ Ò Ñ ×ÙÖ Ò Ñ ÖÓ Ö Ò ×מ Ì Ø ÖÑ Ð Ö ×ÔÓÒ× × Ø Ö ÒØ Ø Ò Ö Ø × Û Ö Ó × ÖÚ Ò Ø Ø Ú Ø ÓÒ Ò Ö × Ó Ø ÔÖÓ ×× × Û Ö Ð ÙÐ Ø ž Ì Ø ÖÑ Ð Ö ×ÔÓÒ× × Û Ö ××Ó Ø Û Ø Ò Ú Ù Ð ÔÖ Ô Ø Ø ÓÒ ÓÖ ×ÓÐÚ ÒØ ÔÖÓ ×× × × ÓÒ ÓÑÔ Ö ×ÓÒ Û Ø Ð Ø Ö ØÙÖ ž ÈÖ Ô Ø Ø ÓÒ × ÕÙ Ò Ó ×Ý×Ø Ñ Å ¹ Û Ö Ó × ÖÚ Ò Ñ Ø Ö Ð× Å ½Ë ½ÅÒ Ò Å ½¼ ½Ë ½ÅÒž ÈÖ ¹ Ô Ø Ø ÓÒ × ÕÙ Ò Ó ×Ý×Ø Ñ Å ¹ Û Ö Ó × ÖÚ Ò Ø Ñ Ø Ö Ð Å ½Ë ½ÅÒž ÈÖ Ô Ø Ø ÓÒ Ó Ô ÖØ Ð × ÅÒ¾Ë Ò Ô ÖØ Ð × ÓÒØ Ò Ò ÅÒ Ò Ê Û Ö Ø ¹ Ø Ò ×ØÙ ÐÐÓÝמ À Ö Ò Ò Û Ö ÒÓØ Ó × ÖÚ Ò Ú ÖØ Ð ×× Ø Ö Û Ö ÒÓØ × Ò ÒØ Ö × × Ó Ö Ò ×× Ò Ø ÙÖ Ò ÒÒ Ð Ò ÙÔ ØÓ ½¼ ž
|
|
|
Influence of deformation on precipitation processes in commercial Al-based alloys with Sc,Zr-addition
Leibner, Michal ; Vlach, Martin (advisor) ; Cieslar, Miroslav (referee)
1 Abstract: Mechanical and thermal properties of Al-5.4wt.%Zn-3.1wt.%Mg-1.5wt.%Cu (AA- 7075), Al-5.2wt.%Zn-3.0wt.%Mg-1.4wt.%Cu-0.2wt.%Sc-0.1wt.%Zr (AA-7075-ScZr) and Al-2.93wt.%Mg-0.34wt.%Mn-0.33wt.%Si-0.22wt.%Fe-0.19wt.%Cr-0.24wt.%Sc-0.06wt.%Zr (AA-5754-ScZr) alloys in as-cast and cold-rolled states were studied by differential scanning calorimetry and microhardness measurements. The initial values of microhardness reflect an effect of cold-rolling. The Sc,Zr-addition caused a pronounced hardening during annealing above ~ 300 řC. An easier diffusion of Zn, Mg, Cu and Mn atoms along dislocations led to a precipitation of Zn,Mg,Cu-containing and Mn-containing particles at lower temperatures in comparison with the AA-7075(-ScZr) and AA-5754-ScZr alloy in the as-cast state, respectively. The Sc,Zr-addition does not significantly influence precipitation of the particles form the Al-Zn-Mg-Cu system.
|
|
|
Characterization of silicone scar treatment gels
Podzimková, Alena ; Šnejdrová, Eva (advisor) ; Miletín, Miroslav (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Author: Alena Podzimková Title of Thesis: Characterization of silicone scar treatment gels Supervisor: PharmDr. Eva Šnejdrová, Ph.D. This diploma thesis deals with characterization of silicone gels by various methods, specifically measurement of rheological properties, overall characterization of the composition by infrared spectroscopy, identification of volatile compounds by gas chromatography and determination of molecular weight distribution of polymers by gel permeation chromatography. The theoretical part provides information about scars and their treatment options and describes the principles and the evaluation of tests performed in the experimental part. Five commercial gels and three newly formulated scar healing gels were evaluated. Analysis of viscosity curves confirmed newtonian type of flow in commercial gels Scar Gel Dr. Max and Stratamed and in the newly formulated gels. Strataderm, RejuvaSil and ScarEsthetique show a decrease in viscosity under stress. Oscillation tests have shown a gel structure only with the commercial ScarEsthetique and RejuvaSil. Scar Gel Dr. Max, Strataderm, the newly formulated gels and Stratamed contain polymeric polydimethylsiloxane. In case of Scar...
|
|
|
Characterization of silicone scar treatment gels
Podzimková, Alena ; Šnejdrová, Eva (advisor) ; Miletín, Miroslav (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Author: Alena Podzimková Title of Thesis: Characterization of silicone scar treatment gels Supervisor: PharmDr. Eva Šnejdrová, Ph.D. This diploma thesis deals with characterization of silicone gels by various methods, specifically measurement of rheological properties, overall characterization of the composition by infrared spectroscopy, identification of volatile compounds by gas chromatography and determination of molecular weight distribution of polymers by gel permeation chromatography. The theoretical part provides information about scars and their treatment options and describes the principles and the evaluation of tests performed in the experimental part. Five commercial gels and three newly formulated scar healing gels were evaluated. Analysis of viscosity curves confirmed newtonian type of flow in commercial gels Scar Gel Dr. Max and Stratamed and in the newly formulated gels. Strataderm, RejuvaSil and ScarEsthetique show a decrease in viscosity under stress. Oscillation tests have shown a gel structure only with the commercial ScarEsthetique and RejuvaSil. Scar Gel Dr. Max, Strataderm, the newly formulated gels and Stratamed contain polymeric polydimethylsiloxane. In case of Scar...
|
guest ::
