National Repository of Grey Literature 27 records found  beginprevious21 - 27  jump to record: Search took 0.00 seconds. 
Pilot study of sublingual in vitro permeation of butorphanol.
Šrámková, Markéta ; Vachek, Josef (referee) ; Doležal, Pavel (advisor)
The theoretical has mentioned the basic information about pain and its treatment. Furthermore, there are described analgesics, mainly opioids. This part is specifically focused on the kinetics and pharmacodynamics of butorphanol alone. A following section deals with the basic description of sublingual administration and it provides with a description of morphology of tongue and also provides information from articles, which dealt with a similar theme as this thesis. The experimental part focuses on the permeability of a sublingual membrane using butorphanol dispersed in different vehicles. Isopropyl myristate, phosphate buffer pH 5.3, propylene glycol - water (3:2) were used. Some of the test donor samples used gelatinous membrane or chitosan donor membrane. Acceptor phase in the experiments was phosphate buffer pH 7.4 or pH 6.5. Permeation marker there was caffeine. I have found from the permeation results obtained that caffeine as a marker of choice was appropriate. Permeability tests of butorphanol brought some interesting findings on the dependence between permeability and a selected membrane type. It can be concluded from the results that the membrane permeability of the membrane affected by membrane properties more than the used vehicle.
Nanofiber membranes as carriers of drugs 6.
Bidmonová, Hana ; Doležal, Pavel (advisor) ; Vachek, Josef (referee)
Rigorous thesis Nanofiber membranes as carriers of drugs 6. Mgr. Hana Bidmonová ABSTRACT Thesis deals with the evaluation of absorption and the release properties of the nanofibre membranes that were prepared using electrospinning of chitosan solution with the contents of 5 % of a drug and covered with polyurethane layer. Thesis brings a survey about the use of nanofibre membranes in pharmacy and medicine, especially their characteristics and application at drug delivery and distribution and in tissue engineering. The ability of three different membranes to accept and release caffeine as a model drug from their structure was investigated. The caffeine was incorporated into the membranes in company Elmarco, Liberec, or it was impregnated in the membranes using absorption from solutions containing drug. A hypothesis concerned with ability of membranes to accept a part of caffeine by another mechanism than an amount incorporated before electrospinning was confirmed. All of three membranes were immersed in media containing caffeine and they adsorbed the drug in quantity dependent on the sort of liquid medium. At the use of the chloroform dispersions of caffeine, membranes adsorbed more then a mass of membranes themselves. In the set of release experiments of membranes the released amount of caffeine...
Nanofiber Membranes as Drug Carriers 5.
Beneš, Michal ; Vachek, Josef (referee) ; Doležal, Pavel (advisor)
M. Beneš Abstract The theoretical part of this work deals with chitosan polymer and its derivates. A polymer molecule is described in more detail, its solubility and chemical modifications are described separately. In the next part biocompatibility and biodegradability of chitosan are dealt with. Parameters of the electrospinning of chitosan end this chapter. The experimental part is first dedicated to the determination of aquosity in the samples of 3 different nanofiber membranes and to their gravimetric changes by keeping in the desiccator. The samples of membranes absorb water at the most up to 1,5% (m/m) and there is not a big difference among them. The second part quantifies changes in the composition of the saturated excipients which were used for the impregnation of the samples of nanomembranes. The highest amount of caffeine was absorbed by the membrane 3, namely in case of both saturating media. The evaluation of the amount of caffeine which the tested membranes are able to release from their surface in vitro follows. In case of the saturation of membranes by the aqueous solution of caffeine and by the caffeine suspension is the maximum of the subsequent liberation into the acceptor phase reached from the 120th minute. In case of the ethanolic and chloroform saturated solution is the maximal...
Effect of Lipophilicity of Substrates and Surfactants on the Efficiency of Micellar Hydrolysis of p-N-nitrofenylalkanoates with Alkylpyridinium Bromides
Běhávková, Vendula ; Vachek, Josef (referee) ; Doležal, Pavel (advisor)
Rigorosum Thesis 2010, Vendula Běhávková Abstract The subject of this work was to verify if a homologous series of N-alkylpyridinium substances and p-nitrophenylcarbonates possess the reciprocal influence of the length of alkyl chains on the rate of hydrolytic reaction. In a series of N-alkylpyridinium substances was tested pyridinium bromide with alkyl chain lengths of C10, 12, 14, 16 and C18. These surfactants were tested with p-nitrophenyl acetate, -butyrate, -caprylate, -caprate, -laurate, -myristate, -palmitate and-stearate. The highest values throughout the group results were achieved through a combination of p-nitrophenyl-caprate and octadecylpyridinium bromide. 5x10-3 M concentration of surfactant was able to accelerate the decomposition of p-nitrophenyl-caprate 120 times and almost reached the rate constant 0.0878 sec-1 , which corresponds to the half-life is approximately 8 seconds. octadecylpyridiniumbromide and hexadecylpyridinium bromide were proved as successful micellar catalysts. The best hydrolysable substrates were medium-length alkylated.
Cleaning Validation Procedures in Manufacturing of Liquid Dosage Forms
Koníková, Veronika ; Doležal, Pavel (advisor) ; Vachek, Josef (referee)
The thesis preamble introduces validations of analytical methods, as an important process during pharmaceutical development and quality control in pharmaceutical manufacturing. Method validation has essential influence on pharmacoeconomics and greatly shortens the time of placing the medicament to the market. The IMS principle greatly shortens analysis time, thus ensuring economic and innovation growth for pharmaceutical companies. Experimental part of this thesis was performed on the device IONSCAN - LS Smiths- Detection, USA in the branch of the Teva company in Opava, which introduces IMS to analytical procedures validation for cleaning validation in pharmaceutical manufacturing. For measuring, the Naphazolini nitras standard was used and the Teflon dry method was applied. During the method development itself, in which I participated, the method usability range was found in the interval of mass concentrations from 0,06 - 0,80 mg / ml. The detection limit at the level of 0.02 ppm and the quantification limit at the level of 0.08 ppm were determined and linearity was verified. In the second part, I validated the analytical method for cleaning process validation. Sampling was performed by means of polyurethane swabs "Large Swab" from a metal plate of surface size 5 x 5 cm2. From this equipment, a...
Study of dispersity of nanoemulsive drug carriers
Hájková, Hana ; Doležal, Pavel (advisor) ; Vachek, Josef (referee)
SUMMERY Theoretical part of this work is focused on explanation of such terms like nanoparticules and nanoemulsions and their usage within peroral and topical administration. Next part explains the merit of zeta potential and DLVO theory, which influence the stability of the elements. Off course, also the principle of the measuring of viscosity is mentioned, because viscosity is taken into consideration in case of measuring of the element dispersion. The experimental part is focused on determination of the partije size by photon correlation spectroscopy by temperature of 25řC and 37řC. The measurement was taken in chronological succession to estimate the stability of dispersion system. It was also measured electrokinetic parameter - zeta potential, which plays a fundamental role by keeping the stability of nanoemulsions. It was proved, that the size of the elements gets settled after approx. 1 week, further changes are not so striking anymore, not even by the increase of temperature to 37řC. Since creating the emulsion (approx. 1 week), the major share of the size of particles (about 60-95%) was ranging between 120-175 nm. As well zeta potencial remains in stable range (+2 mV - -0,6 mV) by the increase of temperature to 37řC and adding of three pH highs of buffers. From the gained results we can draw...

National Repository of Grey Literature : 27 records found   beginprevious21 - 27  jump to record:
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4 Vachek, Jakub
1 Vachek, Jan
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