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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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Formulation of biodegradable nanoparticles containing terbinafine
Čermáková, Věra ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
ABSTRAKT- EN The aim of the thesis was targeted towards the assimilation of preparation method of nanoparticulate systems from biodegradable aliphatic polyester carriers. The procedure based on dispersion and homogenisation of carrier solutions in chlorinated hydrocarbons in aqueous phase was proven. Gelatin hydrolysate and blend of lecithine with plolysorbate were used as komplex emulsifiers. The prepared samples were measured from the aspect of their size and zeta potential values. Reverse dialysis as novel púroposed method of nanosuspensions concentration and following spray drying with manitol carrier were tested by IA method.
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The preparation of oligoester nanoparticles by emulsion method
Šeuerová, Andrea ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
The deal of the work was focused on the study of efficiency of complex emulsifying agent on the nanoparticulate systems preparation by the o/w emulsion-solvent distribution method. Poly (DL-lactic acid) was used as the carrier, terbinafine as a model drug. Complex emulsifying agent was realized by the mixing of soy or egg lecithin with various proportions of nonionic surfactants. Four nonionic surfactants were tested - polysorbate 20, and poloxamers: 470, 6400, and 6800. Optimal compositions in the aspect of nanoparticles minimal size and zeta potential maximal value were stated.
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The size and surface charge of oligoester nanoparticles in the course of their fabrication
Bolek, David ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
1 Summary In the thesis are in details described various methods of pharmaceutical nanoparticles preparation, their surface properties and incorporated drug release. Some relevant data concerning prospective use of nanosystems in pharmacotherapy are presented. The main orientation of the thesis is towards experimental laboratory working. Experiments are supported by the use of Nanosizer and Zetasizer device. Nanoparticles with the size under 200 nm from various oligoesters with the linear and branched constitution of carrier molecules were fabricated. The aim of the thesis was focused on stability of size and surface charge parameters during their storage under different thermal conditions and under static and dynamic state of hydrophilic external phase after preparation process. Liquid systems containing freshly prepared nanoparticles were spray dried with the mannitol used as additive. The processes including range of stress factors, such as mannitol as osmotic agent dissolution, spray drying operation, and nanoparticles contained in microparticles in aqueous medium dispersion were evaluated from the point of view of size and zeta potential parameters. It was concluded from the experimental results that method based on spray drying of nanoparticular systems and incorporation of nanoparticles into the...
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Nanoparticles in pharmaceutical technology : Biodegradable polymeric particles as the systems for drug targeting
Kovácsová, Dana ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
ABSTRACT-EN Emulsion-solvent distribution method was used for the fabrication of nanoparticles with narrow distribution of size parameters. The nanoparticles were prepared from oligoester carriers with various constitution of molecule. Lecithine was successfully proved as emulsifier, its efficiency begins at lower concentration limit of 0.25 %. Efficiently act in emulsification process also blends with nonionic poloxamers and/or polysorbates. These substances was used alone, but only at concentrations under 1% concentration limit. Dichloromethane was also used as proper solvent for this purpose. As novel prospective solvent was used methylacetate. Nanoparticles prepared from methylformate solutions was of non-standard parameters.
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Formulation of extemporaneous paediatric liquid preparations in the hospital pharmacy
Klovrzová, Sylva ; Šklubalová, Zdeňka (advisor) ; Dittrich, Milan (referee) ; Masteiková, Ruta (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Candidate PharmDr. Sylva Klovrzová Supervisor doc. PharmDr. Zdeňka Šklubalová, Ph.D. Title of Doctoral Thesis: Formulation of extemporaneous paediatric liquid preparations in the hospital pharmacy In the paediatric population, oral solutions and/or suspensions represent a suitable alternative to preparation of hard capsules in the pharmacy. This thesis aims at formulation of stable liquid oral preparations with cardiologic drugs, propranol- hydrochloride, sotalol-hydrochloride and furosemide, for the children aged from newborn to approximately 6 year. At the formulation of the preparation compositions, the simple routine preparation in a pharmacy was the main target as well as the use of excipients safe for paediatric population in the minimal necessary amount. Using a high performance liquid chromatography, chemical stability of the active ingredient and, simultaneously, the preservative was determined in all formulated preparations stored at two different temperatures at time points over minimum 180 days. In order to achieve this, the specific analytical methods were developed and validated at the department of Analytical chemistry, Faculty of Pharmacy in Hradec Králové. However, the...
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Drug release from oligoester carriers
Tichopadová, Olga ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
Tichopadová Olga: Drug release from oligoester carriers. Rigorous thesis. Faculty of Pharmacy in Hradec Králové, 2006. The aim of this work was the study of the Terbinafine and Fluconazole release from oligoester carriers branched with 5 % of mannitol (5M) and 30% of dipentaerythritol (3D) and plasticized with various concentration of ethyl pyruvate (EP). The 150,0 mg matrices composed of carrier, drug of 4% and plasticizer EP of 10%, 20% and 30% were prepared. They were put to the static dissolution test using purified water at 37řC. The ACV released was determined spectrophotometricaly at 261 nm in case of Fluconazole respectively 283 nm in case of Terbinafine. Fluconazole was released from carrier 5M linearly from the 1st day to the 4th day of the dissolution test. The complete liberation was finished at the 8th day. Liberation form 3D carrier was slower with the 3-day lag time. Terbinafine release was provided in three stages and was depended on the plasticizer concentration.
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Folic acid release from branched and crosslinked oligoester carriers
Hanáková, Pavlína ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
ABSTRACT-EN In the thesis were demonstrated possibilities for modification of the release period for folic acid incorporated into matrices prepared from poly(DL-lactic acid) branched by mannit or dipentaerythritol. The range of release process duration from two days to 45 days was demonstrated. Process was shortened by increasing concentration of triethylcitrate used as plasticizer of oligoester carrier, the second possibility concentration of branching agent builded into molecule, and the third one was pH of dissolution medium. Prolongation of release of folic acid was achieved by crosslinking agent as additive incorporated into matrices.
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Study of the influence of the pasticizers on acyclovir release from polymeric carriers
Trčková, Kateřina ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
Rigorous thesis Trčková Kateřina 2005 Theoretical part of this work is focused on the polymer delivery systems with controlled released of the drugs and targeting. In the experimental part was studied the Acyclovir (ACV) release from oligoester carriers branched with 5 % of mannitol (5M) and plasticized with various concentration of methyl-, ethyl- or hexyl salicylate. The 150,0 mg matrices composed of carrier, drug of 4% and plasticizer were put to the static dissolution test using phosphate citrate buffer of pH 6,0 at 37řC. The ACV released was determined spectrophotometricaly at 256 nm. The ACV liberation was continuous with different burst effect caused by plasticizer type and concentration. The best release was observed from carriers plasticized using only 10% of the plasticizer despite of the type of plasticizer. Ethyl salicylate in concentration of 10% was found to be the most convenient plasticizer of the 5M carrier.
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