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The use of milling and co-milling procedures for preparation of interactive mixtures
Jezerská, Jana ; Šklubalová, Zdeňka (advisor) ; Kvítek, Libor (referee) ; Vitková, Zuzana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Candidate: Mgr. Jana Jezerská Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Ing. Jakub Koktan, Ph.D. Title of Doctoral Thesis: Utilization of technological procedures of milling and co-milling in the preparation of interactive mixtures The dissertation thesis is an annotated summary of the publication and research activities of the author, Mgr. Jana Jezerská (maiden name Brokešová). The thesis is focused on the preparation of binary interactive powder mixtures which consist of the micronized drug particles adhered onto the larger particles of an excipient (a carrier). The binary powder mixtures were prepared by mixing and/or co-milling and characterized by granulometric methods; crystallinity (thermal analysis, X-ray powder diffractometry), the flow properties (shear cell, avalanche properties) and the surface energy were evaluated as well. The dissolution rate of model drugs was estimated using a flow-through powder dissolution cell (USP-4). The used statistical model (central composite design) enabled to establish optimal milling conditions in a ball mill (the milling speed, the milling time, the size of milling balls) for five powder carriers. Based on quadratic response surface,...
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The use of milling and co-milling procedures for preparation of interactive mixtures
Jezerská, Jana ; Šklubalová, Zdeňka (advisor) ; Kvítek, Libor (referee) ; Vitková, Zuzana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Candidate: Mgr. Jana Jezerská Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Ing. Jakub Koktan, Ph.D. Title of Doctoral Thesis: Utilization of technological procedures of milling and co-milling in the preparation of interactive mixtures The dissertation thesis is an annotated summary of the publication and research activities of the author, Mgr. Jana Jezerská (maiden name Brokešová). The thesis is focused on the preparation of binary interactive powder mixtures which consist of the micronized drug particles adhered onto the larger particles of an excipient (a carrier). The binary powder mixtures were prepared by mixing and/or co-milling and characterized by granulometric methods; crystallinity (thermal analysis, X-ray powder diffractometry), the flow properties (shear cell, avalanche properties) and the surface energy were evaluated as well. The dissolution rate of model drugs was estimated using a flow-through powder dissolution cell (USP-4). The used statistical model (central composite design) enabled to establish optimal milling conditions in a ball mill (the milling speed, the milling time, the size of milling balls) for five powder carriers. Based on quadratic response surface,...
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The preparation of biocompatible silver nanodispersions by the reduction of their solutions
Ulahelová, Jana ; Dittrich, Milan (advisor) ; Kvítek, Libor (referee)
The aim of the thesis was focused into the range of factors influencing the size of silver nanoparticles usable as antimicrobials prepared by Tollens method. This method is based on reduction reaction of silver salts or silver complexes with reduction agents. Mono-, oligo-, and polysacharides are regarded as the most useful compounds for this purpose with regard to their minimal toxicity and high biocompatibility. It was concluded that various hydrodynamic conditions realized via usual stirring by laboratory stirrer, or microwaves source action, or in relatively static conditions, don't influence the condensation process in the different extent. Temperature rising to 85 řC didn't influence the size of nanoparticles also. Polymers and oligomers, as polyvinylalcohol, starches, and polydextroses has been found as the very appropriate reduction agents. The prepared samples consisted of very fine nanoparticles, the size characteristics represented by intensity and volume diameters were in the order of units of nanometers, the polydispersity indexes were of very low values.
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The preparation and evaluation of microparticles containing colloidal silver
Sedláček, Petr ; Dittrich, Milan (advisor) ; Kvítek, Libor (referee)
In the Doctoral thesis is presented theoretical overview of relevant scientific knowledge concerning preparation and use of silver colloidal particles enlarged with technical information concerning drying and quality control methods of dispersion systems. Experimental section of the work is focused on two methodically different areas. The first one is dedicated to newly developed procedure of increasing colloidal silver particles concentration, the second one to the approach to the system stabilization. Kinetics of nanosuspension concentrating is studied and short-time stability of concentrated systems is subsequently monitored. The influence of model adsorption polymers on parameters and behavior of colloidal system is tried. Also nanosystem spray drying method and products image analysis are solved in the thesis.
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Biopharmaceutical aspects of macromolecular carriers for systemic sublingual drug delivery
Berka, Pavel ; Doležal, Pavel (advisor) ; Kubová, Kateřina (referee) ; Kvítek, Libor (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Candidate Mgr. Pavel Berka Supervisor Doc. RNDr. Pavel Doležal, CSc. Title of Doctoral Thesis Biopharmaceutical aspects of macromolecular carriers for systemic sublingual drug delivery The primary aim of this work was to experimentally verify the hypothesis on sublingual permeation of macromolecules as drug carriers. Literature data about the sublingual route of drug administration and methods of sublingual and buccal membrane processing for in vitro experiments were reviewed for this purpose. The task to design and verify a new methodology of processing and preservation of sublingual membranes suitable for permeation experiments resulted from this literature review. The new methodology of the "flash freezing" membranes uses the prepared membranes with complete epithelial composition, including the lamina propria and part of the fibrous substrate. Rapid membrane freezing with liquid nitrogen (-180 řC) was performed without cryoprotectants to avoid affecting membrane permeability, with only preliminary fixation of protein structures with sodium azide. For comparison, membranes were also frozen by conventional slow freezing to -20 řC and declared as "frozen" membranes. Neither "fresh" nor "flash frozen"...
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Medicated polymer systems based on branched PLGA derivatives
Martiška, Juraj ; Dittrich, Milan (advisor) ; Kubová, Kateřina (referee) ; Kvítek, Libor (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Candidate Mgr. Juraj Martiška Supervisor doc. RNDr. Milan Dittrich, CSc. Title of Doctoral Thesis Medicated polymer systems based on branched PLGA derivatives This work is focused on the use of originally synthesized poly(DL lactic-co-glycolic acid) (PLGA) derivatives with relatively low molar mass, and linear, star, or comb architecture as promising biodegradable carriers for prolonged or targeted drug release systems. Thermal properties of these polyesters were evaluated by thermogravimetric analysis and differential scanning calorimetry. Polyesters were used for nanoparticles formulation by nanoprecipitation method, which has been optimized with emphasis on organic solvent selection, polyester concentration, phase mixing speed, and stabilizer selection. After method optimization, nanoparticles with encapsulated terbinafine, a typical drug of the BCS class II, were prepared. Multiple parameters such as particles size, polydispersity index, zeta potential, encapsulation efficiency, loading capacity, and morphology were monitored. Spherical morphology was observed using scanning electron microscopy. The hydrophobicity and the polyester concentration revealed the main impact on the nanoparticles size...
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Biopharmaceutical aspects of macromolecular carriers for systemic sublingual drug delivery
Berka, Pavel ; Doležal, Pavel (advisor) ; Kubová, Kateřina (referee) ; Kvítek, Libor (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Candidate Mgr. Pavel Berka Supervisor Doc. RNDr. Pavel Doležal, CSc. Title of Doctoral Thesis Biopharmaceutical aspects of macromolecular carriers for systemic sublingual drug delivery The primary aim of this work was to experimentally verify the hypothesis on sublingual permeation of macromolecules as drug carriers. Literature data about the sublingual route of drug administration and methods of sublingual and buccal membrane processing for in vitro experiments were reviewed for this purpose. The task to design and verify a new methodology of processing and preservation of sublingual membranes suitable for permeation experiments resulted from this literature review. The new methodology of the "flash freezing" membranes uses the prepared membranes with complete epithelial composition, including the lamina propria and part of the fibrous substrate. Rapid membrane freezing with liquid nitrogen (-180 řC) was performed without cryoprotectants to avoid affecting membrane permeability, with only preliminary fixation of protein structures with sodium azide. For comparison, membranes were also frozen by conventional slow freezing to -20 řC and declared as "frozen" membranes. Neither "fresh" nor "flash frozen"...
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The preparation of biocompatible silver nanodispersions by the reduction of their solutions
Ulahelová, Jana ; Dittrich, Milan (advisor) ; Kvítek, Libor (referee)
The aim of the thesis was focused into the range of factors influencing the size of silver nanoparticles usable as antimicrobials prepared by Tollens method. This method is based on reduction reaction of silver salts or silver complexes with reduction agents. Mono-, oligo-, and polysacharides are regarded as the most useful compounds for this purpose with regard to their minimal toxicity and high biocompatibility. It was concluded that various hydrodynamic conditions realized via usual stirring by laboratory stirrer, or microwaves source action, or in relatively static conditions, don't influence the condensation process in the different extent. Temperature rising to 85 řC didn't influence the size of nanoparticles also. Polymers and oligomers, as polyvinylalcohol, starches, and polydextroses has been found as the very appropriate reduction agents. The prepared samples consisted of very fine nanoparticles, the size characteristics represented by intensity and volume diameters were in the order of units of nanometers, the polydispersity indexes were of very low values.
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The preparation and evaluation of microparticles containing colloidal silver
Sedláček, Petr ; Dittrich, Milan (advisor) ; Kvítek, Libor (referee)
In the Doctoral thesis is presented theoretical overview of relevant scientific knowledge concerning preparation and use of silver colloidal particles enlarged with technical information concerning drying and quality control methods of dispersion systems. Experimental section of the work is focused on two methodically different areas. The first one is dedicated to newly developed procedure of increasing colloidal silver particles concentration, the second one to the approach to the system stabilization. Kinetics of nanosuspension concentrating is studied and short-time stability of concentrated systems is subsequently monitored. The influence of model adsorption polymers on parameters and behavior of colloidal system is tried. Also nanosystem spray drying method and products image analysis are solved in the thesis.
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