Spelling suggestions: "subject:"solid phase"" "subject:"solid chase""
441 |
Stanovení vybraných pesticidů pomocí plynové chromatografie / Assessment of selected pesticides using gas chromatographyMatušková, Monika January 2012 (has links)
The submitted thesis deals with determination of selected pesticides in water samples by gas chromatography. The target pesticides belong to the group of organophosphates (chlorpyrifos, diazinon, parathion, dimethoate, phosmet) and carbamates (carbofuran, aldicarb, methiocarb, pirimicarb, and propamocarb). In the theoretical part, the division of pesticides is stated, and their properties are described, as well as their fate in the environment and their negative effects. Then, the possibilities of analytical determination based on gas chromatography are characterized. The experimental part describes the treatment of the samples and their subsequent analysis. Solid phase extraction was chosen as the extraction technique. Two kinds of cartridges were optimized (Oasis HLB and Supelclean ENVI-18) in combination with various elution reagents. The most suitable combination was then used for processing of real samples of waste-water, which was taken from WWTP in Brno Modřice. For the final determination of the target compounds by gas chromatography, two types of detectors were used: mass spectrometer and an electron capture detector.
|
442 |
Stanovení lineárních syntetických vonných látek v abiotických a biotických matricích / Determination of linear synthetic aromatic compounds in abiotic and biotic matricesTulková, Tereza January 2014 (has links)
Synthetic musk compounds are artificial organic compounds with a smell similar to the odor of a natural musk. The most recently discovered and also the least known group of artificial musks is linear musk compounds. These substances are now often used in cosmetics, personal care products, detergents and various cleaning products. They have leaked into all the major environment components, especially into the hydrosphere. There has been great attention drawn to synthetic musk compounds in the last few years because of their environmental impact. The aim of this thesis is to identify twelve linear musk compounds (linalool, 2-cyclohexylethanol, fresco menthe, citronellol, HSA, isobornyl acetate, arocet, aroflorone, allyl cyclohexyl propionate, lilial, isoamyl salicylate and hexylcinnamic aldehyde) in waste water samples. The samples were taken at three different waste water treatment plants (WWTP) in South Moravian region (WWTP Brno-Modřice, WWTP Luhačovice and WWTP Hodonín). Each of these treatment plants has a different equivalent number of inhabitants. At first, a working method was optimized, then applied on real waste water samples. Solid-phase microextraction (SPME) technique was used for the extraction of analytes. Gas chromatography–mass spectrometry (GC/MS) was then used for identification and quantificaton of the studied compounds.
|
443 |
Stanovení léčiv v pitných vodách metodou HPLC / Determination of pharmaceuticals in drinking waters using HPLCKrálová, Radka January 2015 (has links)
The aim of the diploma thesis is the determination of macrolide antibiotics in drinking water by using of high performance liquid chromatography. Erythromycin and clarithromycin were selected such as representative macrolides due to frequently prescribed pharmaceuticals in this time. Solid phase extraction (SPE) by using of Oasis HLB cartridges was applied for pre concentration and purification of chosen analytes in real samples of drinking water. Optimalization of method and analysis were performed by using of high performance liquid chromatography with mass spectrometry detection (HPLC-MS). The suitable method was selected for determination of macrolides in real samples taken from two sources of drinking water, the interception of water in Litovel and Černovír Olomouc.
|
444 |
Využití kapilární zónové elektroforézy pro stanovení vybraných analgetik ve vodách / Use of Capillary Zone Electrophoresis for Determination of Selected Analgetics in WaterČapka, Lukáš January 2011 (has links)
From viewpoint of environmental analysis in the whole world became popular in the latest years the question of drugs’ breakthrough to the component of environment. These contami-nants belong to the biological active compounds, with different physical-chemical and biolog-ical properties and evince great tendency to bioaccumulation. They penetrate to the environ-ment because of their increasing of usage and wrong techniques of liquidation. The most often use drugs are preparations against pain – analgetics, and from this category there are non-steroidal anti-inflammatory drugs. The frequent usage of this compounds relate to their easy accessibility. From this large group of compounds was chosen for monitoring: diclofenac, ibuprofen, ketoprofen, salicylic acid, naproxen and acetaminophen; because they include in favorite preparations. The monitoring matrix was the wastewater from two waste water treat-ment plants (WWTP). The sampling was performed in inflow and outflow because the com-paring of concentration of selected contaminants and discovering of efficiency of removing the polutants reliance on treatment technology. For extraction of selected contaminants was used solid phase extraction (SPE) and for determination was used capillary zone electrophore-sis (CZE) with diode array detection (DAD). There was identified and quantified all of se-lected analgetics in inflow and so in outflow of WWTP. That means, this polutants infuse into surface water and then into other components of environment.
|
445 |
Studium reverzibilní adsorpce nukleových kyselin na pevných nosičích / Study of Reversible Adsorption of Nucleic Acids on Solid SurfacesTrachtová, Štěpánka January 2011 (has links)
Magnetically driven separation techniques using magnetic solid carriers are one of modern methods to speed up and facilitate the previously used separation and purification procedures. The use of magnetic particles in biology imposes strict requirements on physical, and chemical properties of the particles, including low toxicity, biocompatibility and non-interference with the chemical environment in diagnostics. The aim of this study was to evaluate carboxyl-functionalised magnetic non-porous P(HEMA-co-GMA), P(HEMA-co-EDMA), PGMA, silica-coated lanthanum manganese peroskvite La0.75Sr0.25MnO3 and thermosensitive poly(N-isopropylacrylamide) microspheres – P(NIPAAm) for DNA isolation from different types of complex food and environmental samples containing PCR inhibitors. The solid-phase reversible immobilisation (SPRI) of nucleid acids on microsphere surface and the release of adsorbed DNA were optimised. DNA from real samples (milk products and probiotic food suplements, mouse faeces) was apparently adsorbed on solid particles from the aqueous phase system composed of 16% PEG 6000 and 2M NaCl. The conditions of the subsequent release absorbed DNA to the elution buffer (pH of elution buffer, temperature and time of elution) were optimized. The quality of eluted DNA and the presence of target DNA were examined by PCR and q-PCR using domain-specific Bacteria and genus-specific Lactobacillus primer set. Real-time PCR was used for an estimation of the PCR interference by comparing the amplification efficiencies of purified DNA containing solid nanoparticles with the DNA standards free of any nanoparticles
|
446 |
Alergenní vonné látky v potravinách a předmětech běžného užívání / Fragrance Allergens in Foods and Everyday Use ProductsDivišová, Radka January 2014 (has links)
Fragrances are added to food, cosmetics and other products primarily for enhancement of their sensory quality (taste and/or aroma). However, the usage of these compounds is associated with the wide range of various adverse biological effects. Some fragrances widely used in cosmetics are proved to cause e.g. skin sensitization, rashes, dermatitis, headache, cough etc. To protect the health of consumers, European union approved the cosmetic directive (ES/1223/2009) that requires the labeling of 26 allergen fragrances on the final product label, if concentration exceeds the given level (0,01 % for rinse-off and 0,001 % for leave-on product). However, some producers hide the presence of allergens in the final product under the general term „aroma“. For this reason it is very important to monitor the content of these substances in cosmetic products. Fragrances are found not only in cosmetics, but the various types of food are also aromatized by them. Unlike cosmetics, the food producers are not obliged to label the presence of fragrance allergens on the packaging. Therefore, the monitoring of these fragrances is highly desirable because of the potential health risks they pose. The aim of this study was to develop a method for simultaneous determination of regulated fragrance allergens in food and everyday use products. The method based on extraction of analytes by solid phase microextraction coupled to gas chromatography with FID detection (HS-SPME-GC-FID) was chosen on the basis of the literature review. The fiber CAR/PDMS provided the highest extraction efficiency among the SPME fibers tested. Univariate and multivariate data analysis were used to optimize the main parameters affecting microextraction process. The final method validation was performed in terms of linearity, repeatability, reproducibility, recovery, limits of detection and quantification. The optimized and validated method was applied to a wide range of products including cosmetics, aromatized food and fragranced toys. These products were also subjected to sensory evaluation especially in terms of taste and/or aroma (i.e. flavour), which may be associated with the content of the monitored fragrances. The profile test (EN ISO 13299) and seven-point category ordinal scale (ISO 4121) were used for sensory evaluation.
|
447 |
Vliv technologických procesů na obsah prioritních kontaminantů v čistírnách odpadních vod / Influence of technological processes on the content of priority contaminants in wastewater treatment plantsMikulíková, Iva January 2016 (has links)
Water is one of the most abundant substances on Earth and it is an essential part of our lives. Its pollution has an impact on the whole ecosystem. Polybrominated diphenyl ethersare synthetic persistent organic pollutants used as flame retardants in various commercial and household products. This thesis is focused on assesing the degree of elimination of PBDEs in wastewater treatment plants with different technological processes of purification. The samples were collected in the three wastewater treatment plants in the south-moravian region, that means WTP Brno – Modřice, WTP Mikulov and WTP in VFU Brno.
|
448 |
Stanovení makrolidů v odpadních vodách v průběhu technologií aplikovaných na čistírnách odpadních vod / Determination of macrolides in wastewater during the technology applied to wastewater treatment plantsLandová, Pavlína January 2016 (has links)
Diploma thesis is focused on determination of macrolide antibiotics in wastewater. Environmental contamination with drugs currently represents a major problem. To determine the level of contamination is necessary to develop the appropriate analytical techniques. From the group of macrolide antibiotics were selected four representatives: erythromycin, clarithromycin, azithromycin and roxithromycin due to their frequent use in Czech Republic. For their isolation from wastewater was selected solid phase extraction and for analysis high performance liquid chromatography with mass spectrometric detection was chosen. Under optimized conditions, the ten days analysis of wastewater from the WWTP Brno-Modřice, two days analysis of wastewater from the WWTP Mikulov and one day analysis of wastewater from WWTP of University of Veterinary and Pharmaceutical Sciences Brno was performed.
|
449 |
Voltametrické a amperometrické stanovení 5-nitrochinolinu v pitné a říční vodě pomocí uhlíkové filmové elektrody / Voltammetric and amperometric determination of 5-nitroquinoline in drinking and river water using carbon film electrodeRumlová, Tereza January 2011 (has links)
This work focuses on optimization and application of voltammetric methods for determination of 5-nitroquinoline in model samples of drinking and river water using carbon film electrode (CFE). The advantages of carbon film electrode are primarily its wide potential window in both cathodic and anodic regions and also low environmental stress compared to mercury electrodes. In this contribution, CV and AdSV were used to observe electrochemical processes. For determination of 5-nitroquinoline DPV and FIA were used. Solid phase extraction was investigated as a method for preliminary separation and preconcentration for DPV. Determination of 5-nitroquinoline at CFE is based on cathodic reduction of nitrogroup. This work demonstrates the application of carbon film electrode for determination of 5-nitroquinoline in submicromolar concentrations in model samples of water.
|
450 |
Cílená analýza větvených esterů mastných kyselin pomocí LC/MS / Targeted analysis of branched-chain faty acid esters by LC/MSBřezinová, Marie January 2016 (has links)
Lipidomics as a part of metabolomics is a fast-growing area of research due to the improvement in analytical techniques. This master thesis is focused on lipid extraction techniques optimization, using liquid liquid extraction and solid phase extraction as pre-separation methods and ultra performance liquid chromatography coupled with mass spectrometry for extraction and subsequent identification of branched-chain fatty acid esters (FAHFA - branched-chain Fatty Acid esters of Hydroxy Fatty Acids). This newly discovered class of lipid molecules is associated with insulin secretion, which could improve whole body and local glucose metabolism, providing potential for diabetes 2 type treatment. Solid phase extraction of biological samples was optimized on columns regarding to sorbent composition using reversed phase columns with modified styrene divinylbenzene polymer or octadecyl-bonded polymer and normal phase columns packed with silica gel. Column Strata SI-1 Silica was the most effective for FAHFA separation from biological samples. Chromatographic separation of FAHFA was performed on UPLC Ultimate 3000 RSLC equipped with Kinetex C18 1,7 µm, 2,1 x 150 mm column using gradient program. UPLC was coupled to QTRAP 5500/SelexION, a hybrid, triple quadrupole, linear ion trap mass spectrometer equipped...
|
Page generated in 0.0299 seconds