National Repository of Grey Literature 31,364 records found  beginprevious31355 - 31364  jump to record: Search took 1.24 seconds. 

Development of New Methods for Monitoring of Occurence of Pharmaceuticals in the Environment
Aufartová, Jana ; Solich, Petr (advisor) ; Fiala, Zdeněk (referee) ; Garcia-Campaña, Ana M. (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate Mgr. Jana Aufartová Supervisor Prof. RNDr. Petr Solich, CSc. Title of Doctoral Thesis DEVELOPMENT OF NEW METHODS FOR DETERMINATION OF SELECTED PHARMACEUTICALS IN ENVIRONMENTAL SAMPLES During last decade, the consumption of pharmaceuticals is increasing substantially. At the same time their occurrence in environment is increasing as well. Pharmaceuticals are released into environment by excretion, as conjugated or unchanged active compounds, as unused pharmaceuticals, which are not disposed according to the recommendations (e.g. thrown away into the rubbish or flushed down the toilet). Other possible sources of pharmaceuticals are in the agriculture, livestock and aquaculture. The current water treatment technologies do not remove all traces of pharmaceuticals in wastewaters. Therefore the monitoring of their occurrence in surface and wastewaters become more important. Antibiotics and steroid hormones are a group of drugs used in human and veterinary medicine. The main problem with these groups of substances is the emergence of bacterial resistance, in the case of antibiotics, and the effect on the endocrine system, including the reproductive cycle, in the case of steroid hormones. The...

The contribution to the study of the swelling mechanism of aliphatic oligoesters
Faukner, Antonín ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
This work deals with interaction of oligoester carriers based on DL-lactic-co-glycolic acid, with hydrophilic medium. The interaction results with phenomena of degradation, erosion and swelling of delivery system. The purpose of this work was to quantify water soluble, high osmotically active degradation products generated via hydrolysis in the matrices, and to find a connection between concentration of degradation products and changes of swelling in time. Experiments with two types of branched polymers were realized. The main difference between the both had origin in the concentration of tripenterythritol used as branching monomer and in the blending of this polymer with 20% triethylcitrate used as plasticizer. Matrices differ in size too. The method used included parallel gravimetric monitoring of erosion and swelling of matrices and alkalimetric quantifying of degradation acid hydrolysis products. The last mentioned parameter was obtained by the separation of hydrophilic and lipophilic fractions of matrices between organic and aqueous phase. Narrow correlation between matrices swelling rate and simultaneously proven concentration of hydrophilic oligoesters generated in matrices was established.

Vývoj elektrochemického glutamátového biosenzoru
Doležalová, Julie ; Solich, Petr (advisor) ; Polášek, Miroslav (referee)
DEVELOPMENT OF A GLUTAMATE ELECTROCHEMICAL BIOSENSOR Julie Doležalová (Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague) In cooperation with: Sofia A.L.P. Gomes, Alberto N. Araújo (Department of Physical Chemistry, Faculty of Pharmacy, University of Porto) L-Glutamic acid and monosodium glutamate are used to enhance flavour in food prepared at home, restaurants, and by the food processing industry [1]. Glutamate also plays an important role in many metabolic processes. Nevertheless its use is being kept under certain limits as some people have experienced adverse effects, such as stiffness and tension, after its ingestion. Moreover, some studies demonstrate its connection with the appearance of neurological manifestations, such as Parkinson's and Alzheimer's disease. The determination of L-glutamic acid is therefore of major importance. In this work a novel L-glutamate biosensor was developed using a dehydrogenase enzyme (L-glutamate dehydrogenase). These redox enzyme requires for its activity nicotinamide (NAD(P)+ /NAD(P)H) coenzyme, which reduced form was electrochemically regenerated by the water-soluble dye, methylene green. Graphite electrodes were modified with a poly(methylene green) thin film by means of methylene green electrochemical polymerization...

Voltammetric Determination of 2-Methoxy-5-nitrophenol at Nontraditional Electrodes
Charvátová, Michala ; Dejmková, Hana (referee) ; Fischer, Jan (advisor)
Voltammetric determination of 2-methoxy-5-nitrophenol was studied using DC voltammetry (DCV) and differential pulse voltammetry (DPV) at a carbon film electrode (CFE) and a meniscus modified silver solid amalgam electrode (m-AgSAE). Conditions were found for its determination by DCV and DPV at CFE in Britton - Robinson buffer within concentration range 1.10-4 - 1.10-6 mol.l-1 . Using adsorptive stripping voltammetry (AdSV) m-AgSAE in Britton - Robinson buffer pH 2,0 compound this determined in the concentration range (2 - 10) .10-7 mol.l-1 with a limit of detection 3,6.10-7 mol.l-1 . Using a combination of DPV with solid phase extraction (SPE) for determination of 2-methoxy-5-nitrophenol in river water, limit of detection 6,6.10-8 mol.l-1 was abtained. Using cyclic voltammetry (CV) at m-AgSAE and at CFE mechanism of electrochemical reduction 2-methoxy-5-nitrophenol was proposed.

Development and validation of HPLC method for determination of retinyl esters in human serum using monolithic columns.
Krčmová, Lenka ; Solich, Petr (advisor) ; Šatínský, Dalibor (referee)
DEVELOPMENT AND VALIDATION OF HPLC METHOD FOR DETERMINATION OF RETINYL ESTERS IN HUMAN SERUM USING MONOLITHIC COLUMN Absorption test of vitamin A is used for monitoring of intestinal permeability and may represent a sensitive indicator of intestinal damage. In this study, a simple and rapid reversed- phase high-performance liquid chromatography (RP-HPLC) procedure for selective and sensitive determination of retinol, -tocopherol, retinyl-palmitate and retinyl-stearate in blood serum has been developed and used for the monitoring of intestinal mucosal damage in cancer patients treated with cytotoxic drugs after absorption test of vitamin A. The HPLC instrumentation Series 200 LC from Perkin Elmer (Norwalk, USA) with diode- array detector (DAD) was used for the analysis. Separation of retinol, -tocopherol, retinyl- palmitate and retinyl-stearate were performed using the monolithic column Chromolith Performance RP-18e, 100 x 4.6 mm (Merck, Darmstadt, Germany). The gradient elution was used at the flow rate 3 ml min-1 ; mobile phase methanol:water (95:5) in 0-2.1 min and methanol:2-propanol (60:40) in 2.1-4.9 min. The total time of analysis was 6 min. The injection volume of sample was 20 μl and analysis was done at ambient temperature. The detection of retinol, -tocopherol and retinyl esters was carried out...

The aqueduct under the highway through of the microtunnel
Hoza, Martin ; Kunc, Jaroslav (referee) ; Horák, Vladislav (advisor)
During the construction of water pipeline Strelice is necessary to overcome the D1 motorway. This thesis deals with design of the motorway crossing using trenchless technologies. Combination of pipejacking and shield tunneling is chosen. Static calculation includes determination of the jacking force, proposal of the thrust block and assessment of the reinforced concrete jacking pipes.

Sanitation installation in residential building
Mauerová, Martina ; Bárta, Ladislav (referee) ; Vrána, Jakub (advisor)
This Diploma thesis deals with design sanitation installation in a residential building in Prague. The theoretical part is aimed at determining the calculation of flow in the sup-ply duct according to standards. The work also focuses on the alternative solutions of the given specialization. The computational part and project includes a proposal sani-tary and storm sewer, water supply system and their connection to the current pipes. It is a residential building with four overground floors and with two underground floors.

Sediment deposition in reservoir of Nové Heřminovy dam
Kammermayer, Jan ; Šedivý, Jiří (referee) ; Zachoval, Zbyněk (advisor)
The thesis deals with silting of water reservoir Nové Heřminovy. There's describe design of artificial traffic and evaluate its effectiveness. To determine the flow of sediment into the reservoir with use a partially calibrated one-dimensional numerical model of sediment transport with deformation of bed is made in software HEC-RAS. Silting reservoirs is assessment with two methods, the results are compared and describes their limitations. Reservoirs silting evaluates through volume changes in reservoir storage in time.

Development of stability indicating method for chosen preparation
Chmurová, Klára ; Kastner, Petr (advisor) ; Mokrý, Milan (referee)
1 Abstrakt Development of stability indicating method for chosen preparation(HPLC determination of benzyl alcohol in vaginal cream) Graduation thesis Klára Chmurová Charles University in Prague, Pharmaceutical Faculty in Hradec Králové, Department of Pharmaceutical Chemistry and Drug Control The task was to find out a method of simultaneous determination of benzylkalcohol and imidazol (decomposition product of main substance of cream - clotrimazole). This thesis is intent on determination of benzylalcohol. We were looking for proper modification of the pharmaceutical preparation (vaginal cream), then optimisation of chromatographic conditions and validation of this HPLC method also. The best results were obtained with LiChrosphere RP 18,5 µm column (125 mm x 4,6 mm, SUPELCO, ), methanol : buffer (solution of 250 ml water, 1,05 ml triethylamine and 0,333g natrium hexasulphonate, pH = 7, set up by 85% H3PO4) 30 : 70 (v/v) was used as the mobile phase, flow rate was 1 ml/min. Detection was realised by UV detector with wave length set up on 223 nm. Time of analysis was shorter than 10 min.

Employment of HPLC in the field of drug analysis II.
Holásková, Petra ; Kučera, Radim (advisor) ; Mokrý, Milan (referee)
VYUŽITÍ HPLC V ANALÝZE LÉČIV II. PETRA HOLÁSKOVÁ 69 Vitamins are natural substances found in plants and animals. With few exceptions, the human body cannot synthesize them. Consequently, they must be supplied by the diet or by dietary supplements. Vitamins are essential for the normal growth, vitality, and for the prevention and cure of many health problems and diseases together with other essential nutrients such as proteins, fatty acids and carbohydrates. Vitamins are required only in tiny amounts by organism (micrograms or milligrams per day). Therefore, the methods for their separation and determination should be very sensitive. One possible method is the high performance liquid chromatography equipped with the electrochemical detection. This Diploma Thesis is focused on finding of optimal conditions for separation of folic acid, biotin and vitamin B12. These water-soluble substances belong to the B group vitamins. Their main sources are meat, eggs, brewer's yeast or pulses. The separation was carried out on chromatography column Lichrospher 60, RP - select B (240 x 4.0 mm i.d., 5 μm) obtained from Merck. The analysis was achieved by using the electrochemical detector Coulochem III with sensitivity of 1 μA. The flow rate was set to 1 ml/min and the current inserted on the working electrodes was 600 mV...