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Determination of estrogen pollutants in real water sample by HPLC-UV after solid phase extraction.
Kozlík, Petr ; Coufal, Pavel (referee) ; Bosáková, Zuzana (advisor)
4 Abstract Estrogens are considered to belong to chemicals that negatively affect the endocrine system, even if present at very low concentrations. They are discharged into environment as a result of an increasing application of drugs etc. This work is focused on the separation and quantification of five estrogens, namely estrone (E1), 17β-estradiol (βE2), 17α-estradiol (αE2), 17α-ethynylestradiol (EE2) and estriol (E3) in natural water samples by HPLC-UV method. The chromatographic system consisted of a C18 stationary phase (SunFire® C18, 150 x 4.6 mm, octadecyl bounded to silica gel, particle size 5 µm) and binary mobile phase of acetonitrile/water in various ratios in isocratic separation mode. The effect of acetonitrile content in the mobile phase and flow rate of the mobile phase on retention and separation parameters was tested. Under the optimized separation conditions (acetonitrile/water 40/60 (v/v), 1.3 ml/min), all the compounds were baseline resolved and eluted within 15 min. These experimental conditions were applied to the calibration measurements which were carried out within the concentration range from 0.001 to 1 mg/ml. Limits of detection (LOD) and limits of quantification (LOQ) for the individual estrogens and their mixture (standards dissolved in methanol) were determinated. The detection...
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Determination of hormones in wastewater
Zouharová, Kamila ; Tulková, Tereza (referee) ; Vávrová, Milada (advisor)
The presented theoretical and practical study was focused on a single unit of drugs – hormones. In the present study were characterized in detail hormones as drugs or medical ressource and their mode of effect on the human body. Another important part of this study was focused on the evaluate of the incidence of estrogens in the environment and their possible impact on the aquatic ecosystem, mainly for waste water. The last part of study was processed analytical problems of determination of hormones. There were introduced pre-analytical and analytical methods – methods of isolation of hormones from the waste water and methods of thein final determination, which were based mainly on the separation processes.
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Study of Pharmaceuticals Degradationby Advanced Oxidation Processes
Bílková, Zuzana ; Čáslavský, Josef (referee) ; Beklová, Miroslava (referee) ; Zachariášová,, Milena (referee) ; Vávrová, Milada (advisor)
At present, the issue of occurrence of female sex hormones, estrogens and progestogens, in aquatic ecosystems is often discussed by experts and the general public. These substances of steroid structure can be difficult to remove completely by conventional wastewater and drinking water treatment technologies. In given context advanced oxidation processes based on in situ generation of highly reactive hydroxyl radicals can be a suitable technique. This thesis deals with the study of kinetics and degradation products of photocatalytic decomposition of seven female sex hormones (estrone, -estradiol, estriol, ethinylestradiol, diethylstilbestrol, progesterone and norethindrone). Experiments were conducted in a laboratory glass reactor, which was equipped with an energy efficient UV-A LED light source (365 nm emission wavelength) and an immobilised photocatalyst in a form of TiO2 five-layer film deposited on glass. Model samples of water with the initial hormone concentration of 1 mg·L-1 were used and the degradation process was monitored by an HPLC-MS method. In the given system all compounds of interest except estriol had very significant tendency to be adsorb. In the case of estriol the formal rate constant of photocatalytic decomposition was determined based on the Langmuir-Hinshelwood model for two different initial concentrations, 0.5527 hour-1 (1 mg·L-1) and 0.1929 hour-1 (5 mg·L-1), and by comparison of these values it was found that the higher degraded compound concentration, the slower decomposition (fivefold increase of the initial concentration resulted in the constant decrease to almost one-third). Moreover nine degradation products of estriol photocatalytic decomposition were recorded and their structure was designed based on mass spectra. In the second thematic part of the thesis attention was paid to development of a SPE-HPLC-MS method for simultaneous determination of female sex hormones in water ecosystems, with emphasis on an extraction part optimization. The final samples treatment process included besides extraction with Supel™ Select HLB 200 mg SPE cartridges also mechanical impurities removal, hormones extraction from solids trapped on filtration material, sample acidification and extract purification with Supelclean™ ENVI-Florisil® cartridges. Optimised method was used for determination of female sex hormones in two Brno rivers, Svitava and Svratka. In the most cases the concentration was below the detection or quantification limit.
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Application of passive sampling for the analysis of hormones in drinking water
Remerová, Martina ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The thesis focuses on the use of passive sampling during an analysis of hormones in drinkable water. In the theoretical part there are described selected passive samplers and the sample of the type of POCIS is described at fuller length. The next chapter engages with steroid hormones and an input of estrogenic hormone into the environment. The thesis contains chapters dealing with possibilities of the determination of hormones in water. It is specialized on the analysis of drinkable and surface water. In the last chapter of the theoretical part there are introduced water works where samples for an experimental assessment were collected from. The experimental part of the thesis presents the specification of the extraction of analytes and an adjustment of used device. In the thesis there are specific calibrations for individual assessment of hormones. The results of the assessment for each collection point are ordered to a well-arranged table. Increased levels of targeted estrogens were not approved in most of sampling points.
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Hormones and their presence in environmental
Sučková, Tereza ; Dvořáková, Petra (referee) ; Vávrová, Milada (advisor)
This thesis deals with the issue of hormones in the environment and analytical methods for the determination of hormonal substances in water and soil ecosystems. The thesis includes an overview of important hormone groups (divided into categories according to their chemical structure) and basic information about properties of chosen hormones, their sources and impacts on the environment. The next focuses upon methods of determination of hormones in soil and water ecosystems. Finally, a standard operational manual for analysis of estrogens in surface water has been created and is provided herein.
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