National Repository of Grey Literature 137 records found  previous11 - 20nextend  jump to record: Search took 0.01 seconds. 
Importance and impact of phthalates during peritoneal dialysis and current possibilities of their replacement
Nohelová, Gabriela ; Zlámalová Gargošová, Helena (referee) ; Čáslavský, Josef (advisor)
This thesis deals with the importance and influence of phthalates in peritoneal dialysis (PD) and the current possibilities of their replacement. The information about phthalates – esters of phthalic acid - was completed with focus on the most commonly used plasticizer in medical material, bis(2-ethylhexyl) phthalate (DEHP) and its effects on the human organism and the environment. The possibilities of substitution of PVC in peritoneal dialysis were searched and their advantages and disadvantages were evaluated. As the evidence of phthalates absorbed by the human body in carrying out peritoneal dialysis selected studies performed in Germany and in our country, dealing with this issue, were used. High performance liquid chromatography (HPLC) with UV detection at 224 nm or gas chromatography - mass spectrometry (GC / MS) was used here for the determination of phthalates in the blood and dialysate in peritoneal dialysis. Extraction of sample with the suitable solvent and purification of the extract predates the actual analytical determination of sample.
Study of selected antibiotics sorption on polyhydroxybutyrate
Amrichová, Anna ; Doležalová Weissmannová, Helena (referee) ; Řezáčová, Veronika (advisor)
The bachelor thesis deals with the issue of sorption of antibiotics on microplastics. Antibiotics and microplastics are now a highly studied topic, due to the positive and negative properties. Antibiotics with groups of sulfonamides and quinolones were selected for the experiment. From sulfonamides, sulfamethoxazole and trimethoprim were selected, and from the quinolones, enrofloxacin and ciprofloxacin, which have already been the impetus for some microplastic studies. Biodegradable polyhydroxybutyrate was used as the microplastic. Two experiments were performed in the laboratory. The first aimed to monitor the time dependence of antibiotic sorption on polyhydroxybutyrate, the second the concentration. The concentration dependence was subsequently evaluated using the Freundlich and Langmuir isotherms. The method of liquid chromatography with mass spectrometry was used for analyzes.
Application of separation methods with mass spectrometric detection for the study of degradation products of new polymeric materials
Čumová, Martina ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Synthetic polymer materials have been a part of human life since the 20th century. A variety of their use had resulted in a growing demand for their mass production, which then led to their increasing accumulation at waste dumps. After their deposition, these materials are exposed to many environmental factors causing their decomposition and subsequent release of the degradation products into the environment. This thesis is focused on the analysis of the photodegradation products from synthetic polymer materials and particularly polyurethane foams modified with the biodegradable fillers. One dimensional GC/MS and two dimensional comprehensive gas chromatography with time-of-flight mass spectrometry (GCxGC/TOF-MS ) were used for the measurements. The most of photodegradation products of polyurethane foams are injurious to health and environment.
Possibilities of identification of flavonoids in environmental matrixes
Magdechová, Andrea ; Zlámalová Gargošová, Helena (referee) ; Vávrová, Milada (advisor)
Inherent part of plants are active substances; flavonoids belong to this group. They are used in medicine, cosmetics and they shloud be a part of our diet because of their positive effects. This bachelor thesis is focused on the identification of flavonoids in selected types of coniferous trees and moss. Pines, firs and spruces were selected as the representants of coniferous trees, together with mosses Polytrichum formosum and Rhytidiadelphus subpinnatus. Flavonoids were isolated using liquid-liquid extraction and identified using thin layer chromatography and high-performance liquid chromatography.
Assessment of contamination of sewage sludge from wastewater treatment plant by drug residuals
Dvořáková, Petra ; Stoupalová, Michaela (referee) ; Vávrová, Milada (advisor)
The aim of diploma thesis was finding of the method for the determination of drug residua in sewage sludge from wastewater treatment plant. Selected sulfonamide and diaminopyrimidine antibiotics, which are used in human and veterinary medicine, were selected as target comopounds. They are discharged to the sewer systems together with the urine and faeces and enter the sewage treatment plant, where they are not completely removed. They can be found in treated waste water or in sewage sludge. They can enter to the environment, where they can induce negative effects on organisms in soil and water ecosystem. An optimized method was used for identification and determination of these antibiotics in real samples from the large-scale waste water treatment plant in Brno-Modřice and from the waste water treatment plant situated in the area of Veterinary and Pharmaceutical University Brno. Antibiotics were extracted from sewage sludge by ultrasonic and by pressure solvent extraction (PSE). Waste water and sewage sludge real samples were concentrated and cleaned by solid phase extraction (SPE). For determination these antibiotics high performance liquid chromatography with diode array detector (HPLC - DAD) was used.
Use of selected toxicity tests on organisms Eisenia fetida in assessing ecosystem contamination by selected drugs.
Kašpárková, Petra ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Constantly increasing consumption of drugs leads to the increase of the concentration of residues in various environmental compartments. For this reason the drug residues are nowadays classified as significant environmental contaminants. The drug residues enter the soil along with the application of sewage sludge either as a fertilizer or during fertilizing by animal excrements excreted after drug administration, eventually by direct contamination from treated grazing animals. The presence of these substances in soil has got negative impact on the sensitive soil ecosystem. The diploma thesis aims to evaluation of possible soil contamination with selected drugs through ecotoxicity tests. For this purpose sulfonamide chemotherapeutic agents, which are often used in veterinary medicine, were chosen, specifically sulfamethoxazole and sulfamethazin. Eartworms (Lumbricus) were selected as suitable test representative soil organism. In the experimantal part of this work the avoidance test according to ISO 17512-1 and modified bioaccumulation test according to OECD 317 methodology were performed. Bioaccumulation substances in oligochaetes, for which the artificial soil was prepared according to OECD 207 methodology, which was subsequently contaminated with above specified drugs. Although according to the results of determination of these substances there is no significant bioaccumulation in eartworms‘ tissue, these organisms are very responsive to the presence of contaminants in the soil environment. This is evident from the results of avoidance tests.
Portable and Miniaturized Separation Techniques Applicable for Food and Biotechnology Analysis
Dvořák, Miloš ; Pospíchal, Jan (referee) ; Bednář,, Petr (referee) ; Rittich, Bohuslav (advisor)
Capillary electrophoresis was used for determination of 6 fractions of caseins. Those fractions were measured in 144 samples of cow’s milk originated from the feeding experiment focused on explanation the influence of the feeding onto casein productions. In this work were separated 6 fraction of caseins first time with total resolution of the peaks. Capillary electrophoresis was applied for determination of short-chain organic acids during fermentation of wine must. It was compared the fermentation of must fermented by different yeast. The difference of profile short-chain organic acids during fermentation were not statistically significant. The once difference was in the utilisation of the malic acid and production of the lactic acid. A portable miniaturized system for medium pressure liquid chromatography was developed. The components were tested and system was used for the isocratic and gradient elution of various analytes (food dyes, parabens). New line of electroluminescent diodes (LEDs) for deep-UV areas of wavelength based on a different materials substrate was characterised. The new line was compared with old line LEDs. The new line LEDs was incorporated in deep-UV absorbance detectors. Detectors were characterised and tested for a detection various analytes in modes flow injection analysis and chromatography separation. First time was characterised this new line of the LEDs and the origin of the parasitic emission band produced by deep-UV LEDs light sources was explained. This origin is given by disturbances of a materials substrates. This work is a contribution for an advance of low-cost and portable systems and detection devices in the field of analytical chemistry.
The issue of determining antidepressants
Kočnar, Michal ; Tulková, Tereza (referee) ; Vávrová, Milada (advisor)
The presented bachelor thesis is focused on the issue of antidepressants and the determination of two of their representatives, paroxetine and citalopram, in sewage taken from three municipal waste water treatment plants. In the theoretical part of this study, antidepressants are generally characterized, more specifically two representatives of selective serotonin reuptake inhibitors, paroxetine and citalopram. Subsequently, the methods of determination of these analytes in waste water are presented. The experimental part deals with determination of selected substances in real samples of waste water. The analytes were isolated from the matrix by solid phase extraction and determined by ultra performance liquid chromatography with ultraviolet spectrophotometric detection. Paroxetine was quantified in all samples, citalopram was not able to quantify, in some samples even to detect.
Analysis of organic dye degradation product after decomposition in diaphragm discharge
Nejezchleb, Martin ; Friedl, Zdeněk (referee) ; Čáslavský, Josef (advisor)
The diploma thesis is focused on the identification of degradation products of organic dye Saturn Red L4B resulting by degradation in diaphragm discharge, using separation techniques with mass spectrometric detection.
Extraction of antioxidants from the elderberry blossom and preservation of the extract for further possible use
Krůzová, Sabina ; Němcová, Andrea (referee) ; Vespalcová, Milena (advisor)
The thesis deals with the extraction of antioxidants from elder flowers and the way of storage obtained extract. The elder flowers which are obtained by cutting trees as a waste product and after their processing it could be used as an ingredient to cosmetics products for body and face skin or in a spa like additive to baths. In theoretical part are information about black elder, its botanical characteristics, utilization and about substances contained in it. There is also a chapter about lyophilization as a method which was used for concentration of extract. The last chapter describes theoretical information about liquid chromatography because this method was used for analysis of contents of extract. Experimental part describes optimalization steps in preparation of extract. It was found that the biggest content of polyphenolic compounds was when the proportion between flower and water was 1:10, optimal temperature of water for extraction is 100 °C and it was also found that the time of extraction don´t have any influence on content of polyphenols. Thanks to the lyophilization it was obtained dry light brown powder which is stable for long time. The lyophilizate was tested for some physical properties like pH, refractive index, solubility etc. There was also determined antioxidant activity by DPPH method and there was found quenching activity is 64,9 %. In determining of heavy metals in sample was found trace amounts of lead and chrome. By liquid chromatography was determined content of polyphenols, caffeic acid was in an amount 59,6 mgl1, chlorogenic acid 398 mgl1 and ferulic acid wasn´t detected. All of analysis was for 1% solution of extract because to cosmetic it could be just this amount to addition. In the last step was prepared a skin lotion with elder flower extract and it was tested for stability also was prepared an ointment from pork lard.

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