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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Metodologias para determinação de fármacos, metabólitos e disruptores endócrinos em água de abastecimento público utilizando técnicas de separação em meio líquido (CE/UV, CE-MS, LC-MS/MS) / Methods for determination of pharmaceuticals, their metabolites and endocrine disruptors in surface water using separation techniques in liquid media (CE/UV, CE-MS, HPLC-MS/MS)

Ana Carolina de Oliveira Costa 03 December 2009 (has links)
Este trabalho apresenta o desenvolvimento e validação de métodos analíticos para investigar a presença de fármacos e seus metabólitos, assim como disruptores endócrinos, em amostras de águas superficiais, utilizando estratégias de \"clean up\" e enriquecimento de amostra no modo \"on line\" (\"stacking\") e \"off line\" (extração em fase sólida, SPE), em junção com técnicas de separação avançadas em meio líquido (eletroforese capilar, CE, e cromatografia a líquido, LC, com detecção UV, e seus acoplamentos com espectrometria de massas). No primeiro Capítulo são discutidos aspectos gerais sobre os produtos farmacêuticos, produtos de higiene pessoal e disruptores endócrinos, bem como a origem e ocorrência destas substâncias no meio ambiente. O segundo Capítulo aborda o desenvolvimento de um método de separação capaz de determinar oito substâncias entre fármacos de caráter ácido e metabólitos (diclofenaco, bezafibrato, fenoprofeno, ibuprofeno, cetoprofeno, naproxeno e ácidos gentísico e salicílico) numa única corrida, utilizando eletroforese capilar com enriquecimento em linha da amostra (stacking do analito baseado em grande volume de injeção da amostra) utilizando eletrólito de corrida constituído por 30 mmol L-1 de tetraborato de sódio e 5 mmol L-1 de Brij 35, pH 9,3. O método proposto alcançou limites de detecção que variaram de 2 µg L-1 para o fármaco naproxeno até 80 µg L-1 para o ibuprofeno. No terceiro capítulo é explorado um método de separação por CE para nove substâncias entre fármacos e hormônios (fluoxetina, trimetoprima, diazepam, carbamazepina, propranolol, clofibrato, fenofibrato, etinilestradiol e estrona). Utilizou-se como estratégia de pré-concentração dos analitos, o modo \"stacking\" de micelas com grande volume de injeção de amostra. Este método chegou a limites de detecção na ordem de 9 µg L-1 com eletrólito de corrida composto por 30 mmol L-1 de ácido fosfórico, 40 mmol L-1 de dodecilsulfato de sódio, 20% (v,v) de acetonitrila e 0,1% (v,v) de trietilamina. No quarto capítulo, foi realizado o estudo de parâmetros físico-químicos que estão relacionados à técnica de extração em fase sólida, tais como tipo do sorvente, volume de capacidade, volume de eluição, lavagem do cartucho de extração, entre outros. As condições ótimas de \"clean up\" e pré-concentração \"off line\" da amostra obtidas foram combinadas com as condições ótimas de pré-concentração \"on line\" e separação descritas nos Capítulos 2 e 3, para todas as substâncias abordadas ali, com o intuito de analisar amostras reais de água superficial coletadas no reservatório Billings (Estado de São Paulo). O método combinado permitiu alcançar concentrações da ordem de 500 ng L-1, com valores de recuperação satisfatórios (58 - 88%), quando levada em consideração a origem complexa da matriz ambiental. No quinto capítulo, desenvolveu-se um método de análise de p-hidroxibenzoatos de alquila, substâncias utilizadas como conservantes em diversos produtos de uso diário, utilizando eletroforese capilar associada a estratégias de concentração \"on line\" (stacking com injeção de grande volume de amostra) e \"off line\" (SPE). O método proposto, utilizando eletrólito constituído por 40 mmol L-1 de glicina e 40 mmol L-1 de trietilamina, foi aplicado na análise destas substâncias em amostras de água superficial, alcançando níveis de concentração da ordem de 4 6 µg L-1. O sexto capítulo aborda o desenvolvimento de um método por eletroforese capilar destinada à análise de alquilbenzeno sulfonato linear (LAS) e homólogos, tensoativo comumente utilizado na composição de detergentes de uso doméstico e industrial. O eletrólito de separação era composto de 60 mmol L-1 TRIS, 30 mmol L-1 HIBA, 15 mmol L-1 Brij 35 e 40% (v,v) acetonitrila. Foi realizada uma etapa de extração em fase sólida (C18), e uma concentração total de LAS na ordem de 1,09 mg L-1 foi encontrada em uma amostra de efluente de estação de tratamento de esgoto. No capítulo 7 foi desenvolvido um método utilizando eletroforese capilar acoplada a um espectrômetro de massas, com analisador \" ion trap\", para a análise dos fármacos cimetidina, propranolol, salbutamol, trimetoprima e metoclopramida. Amostras de água coletadas no reservatório Billings foi fortificada com os fármacos em estudo e submetida a procedimento de extração em fase sólida em cartuchos de poliestireno divinilbenzeno (PS-DVB). O método permitiu a análise das substâncias estudadas na concentração aproximada de 40 µg L-1. Finalmente, no oitavo capítulo foi explorado um método envolvendo cromatografia líquida de alta eficiência, hifenada a dois tipos de espectrômetros de massas: um triplo quadrupolo e um triplo quadrupolo com \"ion trap\" linear. Foram investigados fármacos de diversas classes em amostras de água coletadas no reservatório Billings, sendo possível encontrar carbamazepina na concentração de 20 ng L-1, com apenas uma etapa de filtração da amostra antecedendo a análise, utilizando o triplo quadrupolo. Cabe destacar que o LOD para este analito foi de 400 fg L-1, sem nenhum tratamento da amostra visando préconcentração. / This work presents the development and validation of analytical methods to investigate the presence of pharmaceutical compounds, their metabolites and endocrine disruptors in surface water using on line (stacking) and off line (solid phase extraction) sample clean up and enrichment strategies coupled to advanced separation techniques in liquid medium (capillary electrophoresis and liquid chromatography with UV detection and their hyphenation with mass spectrometry). In the first Chapter, general aspects on pharmaceuticals, products of personal care and endocrine disruptors are discussed as well as their origin and means of entry to the environment. Chapter 2 describes the development of a separation method for the determination of eight pharmaceuticals and endocrine disruptors substances with acidic character (diclofenac, bezafibrate, fenoprofen, ibuprofen, ketoprofen, naproxen, gentisic and salicylic acids) in a single run using capillary electrophoresis with on line sample enrichment (analyte stacking with large sample volume injection) in electrolytes composed of 30 mmol L-1 sodium tetraborate at pH 9.3 and 5 mmol L-1 Brij 35. The proposed method reached limits of detection between 2 µg L-1 (naproxen) and 80 µg mL-1 (ibuprofen). In Chapter 3, a CE separation method for the determination of nine pharmaceuticals and hormones with neutral and basic character (fluoxetin, trimethoprim, diazepam, carbamazepine, propranolol, clofibrate, fenofibrate, ethynylestradiol and estrone) was exploited. As preconcentration strategy, micelle stacking with large sample volume injection was performed. Limits of detection in the order of 9 µg L-1 were reached with electrolytes composed of 30 mmol L-1 phosphoric acid, 40 mmol L-1 sodium dodecylsulfate, 20% (v,v) acetonitrile and 0.1% (v,v) triethylamine. In Chapter 4, the physicochemical parameters associated with the solid phase extraction technique, such as sorbent type, breakthrough volume, elution volume, extraction cartridge rinse, among others, were evaluated. Optimum sample clean up and off line preconcentration conditions combined with the optimum on line preconcentration and separation conditions described in Chapters 2 and 3, for all substances under consideration, were applied to the analysis of real surface water samples collected at the Reservoir Billings (Sao Paulo state, Brazil). The combined method reached concentrations in the order of 500 ng L-1, with satisfactory recoveries (58 88%) for complex environmental matrices. In Chapter 5, a method for the analysis of alkyl p-hydroxybenzoates, substances used as preservatives in several products of personal care, was developed using capillary electrophoresis associated with on line (stacking with large volume injection) and off line (SPE) preconcentration strategies. The proposed method, which used 40 mmol L-1 glycine and 40 mmol L-1 triethylamine as electrolyte, was applied to the analysis of alkyl p-hydroxybenzoates in surface water, reaching 4 - 6 µg L-1 concentrations. Chapter 6 describes the development of a CE method for de analysis of linear alkylbenzene sulfonates (LAS) and homologues, surfactants commonly used in the composition of detergents of industrial and domestic use. As separation electrolyte, 60 mmol L-1 TRIS, 30 mmol L-1 HIBA, 15 mmol L-1 Brij 35 and 40% (v,v) acetonitrile was used. A solid phase preconcentration extraction step in C18 was employed and a total LAS concentration of 1.09 mg L-1 was found in a sample obtained from the effluent of a sewage treatment plant. In Chapter 7, a CE-MS (ion trap) method was developed for the analysis of cimetidine, propranolol, salbutamol, trimethoprim and methoclopramide in fortified surface water samples collected in the Reservoir Billings (Sao Paulo state, Brazil) and previously enriched by SPE (PS-DVB). The method reached concentrations of c.a. 40 µg L-1. Finally, in Chapter 8, a method based on high-performance liquid chromatography coupled with two different mass spectrometers: a triple quadrupole and a triple quadrupole with linear ion trap). Several pharmaceuticals were investigated in surface water samples collected from the Reservoir Billings (Sao Paulo state, Brazil). With the LC-MS/MS (triple quadrupole) system, carbamazepine was found in a non treated sample (just a filtration step prior to injection was performed) in a concentration level of 20 ng L-1. It is worth mentioning that for carbamazepine, a LOD of 400 fg L-1 was found, without any preconcentration sample treatment
172

\"Verificação da janela de detcção do etilglicuronídeo urinário entre usuários crônicos e bebedores sociais de etanol por cromatografia em fase gasosa acoplada à espectrometria de massas\" / Detection range verification of urinary ethyl glucuronide between chronic ethanol users and social drinkers by gas chromatography/mass spectrometry analysis

Ana Verónica Flores Marin 06 July 2006 (has links)
A janela de detecção de etilglicuronídeo (EtG) parece variar de acordo com a intensidade de consumo de etanol. Assim sendo, o objetivo do presente trabalho foi desenvolver e validar uma metodologia empregando extração em fase sólida e GC-MS para a determinação de EtG urinário, no sentido de verificar sua janela de detecção entre um grupo de bebedores sociais e usuários crônicos. Os limites de detecção e quantificação obtidos foram 0,1 e 0,2 mg/L respectivamente. O método proposto demonstrou ser linear no intervalo de 0,2 a 100,0 mg/L (r2>0,99), exato e preciso. A janela de detecção de EtG em amostras de urina de cinco voluntárias após ingestão única e controlada de 0,5 g/kg de etanol variou de 24 a 35 horas. Amostras de urina foram coletadas de 14 pacientes internados em clínica de recuperação. Os resultados mostraram que a maioria deles provavelmente consumiu etanol, prejudicando a interpretação dos resultados. Nos casos em que a concentração urinária de EtG foi decaindo no decorrer do tempo, a janela de detecção variou de 72 a 120 horas. O método mostrou ser útil para monitorar a abstinência durante o tratamento de pacientes dependentes de etanol ou o consumo após uma única exposição em baixa dose. / The detection range of the ethylglicuronide (EtG) seems to vary in accordance to the intensity of ethanol consumption. Thus, the objective of the present work was to develop and validate a method using extraction in solid phase and GCMS for the determination of urinary EtG, in order to verify its detection window in a group of social drinkers and chronic ethanol users. The limits of detection and quantification were 0,2 and 0.1 mg/L, respectively. The method showed to be linear in the interval of 0,2 to 100,0 mg/L (r2>0,99), and presented good accuracy and precision. The urinary EtG detection range in samples of five volunteers after controlled ingestion of 0,5 g/kg of ethanol varied between 24 to 35 hours. Urine samples were also collected from 14 patients from a recovery clinic. The results showed that the majority of them probably consumed ethanol, which compromised the interpretation of the results. In the cases where the urinary concentration of EtG decayed with time, the detection window varied from 72 to 120 hours. The method showed to be useful to monitor the ethanol abstinence during treatment of alcoholic patients or the consumption of only one ethanol low dose.
173

Novas abordagens para exploração de reações químicas relativamente lentas em sistemas de análises em fluxo. Aplicações a amostras de relevância agronômica e ambiental / Novel approaches for exploiting relatively slow chemical reactions in flow analysis systems. Applications to relevant agronomic and environmental samples

Ana Clara Felix Vida 27 November 2015 (has links)
Diferentes estratégias foram projetadas e desenvolvidas para sistemas de análises em fluxo envolvendo reações químicas relativamente lentas. O aprisionamento da zona da amostra na bobina de reação permite melhorias de sensibilidade em métodos espectrofotométricos em fluxo envolvendo reações catalíticas. Uma característica inerente a esta estratégia é que, de acordo com as baixas concentrações do analito de interesse esperadas nas amostras, pode-se explorar tanto a variação do tempo quanto da temperatura de aquecimento para o desenvolvimento reacional. Esta estratégia evita a geração de bolhas de ar quando temperaturas elevadas são empregadas. O aprisionamento da zona da amostra na bobina de reação em sistema de análises por injeção em fluxo foi aplicado à reação de oxidação do reagente Tiron por peróxido de hidrogênio catalisada por Co(II) para determinação espectrofotométrica de cobalto em gramíneas. O sistema apresentou boas figuras de mérito, tais como repetibilidade [d.p.r. = 0,8% para 0,6 ?g L-1 Co(II), (n = 5)], limite de detecção [0,046 ?g L-1 Co(II)], frequência de amostragem (19 h-1) e consumo de reagente (330 ?g de Tiron por determinação). Os dados de recuperação nas amostras de gramíneas digeridas variaram entre 97% e 113%. O aquecimento explorando o aprisionamento da zona da amostra na cubeta de detecção mostrou-se promissor para implementação de reações relativamente lentas sem a geração de bolhas de ar, e não houve liberação de bolhas mesmo sob a temperatura de 95ºC. Esta estratégia foi aplicada à determinação espectrofotométrica de vanádio em águas minerais envolvendo a oxidação de p-anisidina por bromato catalisada por V(V) e ativada por Tiron. Sob temperatura de 95ºC, boas figuras de mérito foram obtidas, tais como limite de detecção (0,1 ?g L-1), repetibilidade [d.p.r. = 2,1 % para 5,0 ?g L-1 (n = 10)], frequência analítica [25 h-1] e consumo de reagente (3,0 mg de p-anisidina por determinação). Adicionalmente, foi desenvolvido um procedimento analítico em fluxo para monitoramento dos resíduos de ametrina e atrazina potencialmente lixiviáveis em solos, envolvendo também um processo relativamente lento. Um sistema de análises por injeção sequencial foi utilizado para as etapas de dessorção dos herbicidas com solução 0,01 mol L-1 CaCl2 e concentração em fase sólida em linha, seguida da eluição dessas espécies para a separação em uma coluna monolítica C18 conectada a um cromatógrafo líquido por meio de uma válvula de seis vias. Os eluatos eram injetados no cromatógrafo por meio de uma alça de amostragem de 300 ?L conectada à válvula. Boas figuras de mérito foram obtidas, tais como fatores de enriquecimento de 10,2 e 18,8 e limites de detecção de 0,016 e 0,015 mg L-1 para ametrina e atrazina, respectivamente, limite de quantificação de 0,05 mg L-1 para ambos os herbicidas e repetibilidade estimada como 6,3% e 5,1% para 0,05 mg L-1 (n = 10) para ametrina e atrazina, respecivamente. Os dados de adição e recuperação dos herbicidas nos extratos de solos em condições de equilíbrio se situaram na faixa de 85 a 99% / Different approaches to analytical flow systems involving relatively slow chemical reactions were developed. Zone trapping inside the reaction coil enables sensitivity improvements in flow-based spectrophotometric procedures relying on catalytic reactions. The reaction time and/or temperature can be increased for the determination of analytes present in the samples at low concentrations. Exploitation of the strategy avoids the liberation of air bubbles in the analytical path when high temperatures are involved. A flow injection system with zone trapping in the main reactor was developed for the spectrophotometric determination of cobalt in grass samples exploiting the oxidation of Tiron by bromate catalised by Co(II). Good figures of merit such as repeatability [r.s.d. = 0.8% for 0.6 ?g L-1 Co(II), (n = 5)], detection limit [0.046 ?g L-1 Co(II)], sampling frequency [19 h-1] and reagent consumption (330 ?g of Tiron for determination) were attained. Recovery data in grass sample digests varied within 97% e 113%. Zone trapping inside the flow-through cuvette for exploiting high temperatures was also promising for relatively slow reactions, as no liberation of air bubbles was noted even for temperatures as high as 95oC. The approach was applied to the spectrophotometric determination of vanadium in mineral water samples relying on the oxidation of p-anisidine by bromate catalised by V(V) at 95ºC. Good analytical figures of merit such as repeatability [r.s.d. = 2.1% for 5.0 µg L-1 V(V), n = 10], detection limit [0.1 µg L-1 V(V), sample frequency (25 h-1) and reagent consumption (3.0 mg of p-anisidine per determination) were attained. Additionally, an analytical procedure to monitor the potentially leachable ametryn and atrazine residues in soil samples was proposed. As leaching is relatively slow, a sequential injection system was used to perform the herbicide extractions with 0.01 mol L-1 CaCl2 and in-line solid phase extraction followed by elution towards a C18 monolithic column connected to a liquid chomatograph. To this end, the outlet of the column was connected to a 300-µL six-port valve. Regarding analytical performance, enrichment factors and detection limits were 10.2 and 18.8 and 0.016 e 0.015 mg L-1 for ametryn and atrazine, respectively, quantification limits were 0.05 mg L-1 for both herbicides and good repeatability (r.s.d. = 6.3 and 5.1 % for 0.05 mg L-1 of ametryn and atrazine, n = 10) were attained. Recovery data in the soil extracts under equilibrium conditions were within 85 and 99%
174

Analysis of Clinically Important Compounds Using Electrophoretic Separation Techniques Coupled to Time-of-Flight Mass Spectrometry

Peterson, Zlatuse Durda 16 April 2004 (has links)
Capillary electrophoretic (CE) separations were successfully coupled to time-of-flight mass spectrometric (TOFMS) detection for the analysis of three families of biological compounds that act as mediators and/or indicators of disease, namely, catecholamines (dopamine, epinephrine, norepinephrine) and their O-methoxylated metabolites (3-methoxytyramine, norepinephrine, and normetanephrine), indolamines (serotonin, tryptophan, and 5-hydroxytryptophan), and angiotensin peptides. While electrophoretic separation techniques provided high separation efficiency, mass spectrometric detection afforded specificity unsurpassed by other types of detectors. Both catecholamines and indolamines are present in body fluids at concentrations that make it possible for them to be determined by capillary zone electrophoresis coupled to TOFMS without employing any preconcentration scheme beyond sample work up by solid phase extraction (SPE). Using this hyphenated approach, submicromolar levels of catecholamines and metanephrines in normal human urine and indolamines in human plasma were detected after the removal of the analytes from their biological matrices and after preconcentration by SPE on mixed mode cation-exchange sorbents. The CE-TOFMS and SPE methods were individualized for each group of compounds. While catecholamines and metanephrines in urine samples were quantitated using 3,4-dihydroxybenzylamine as an internal standard, deuterated isotopes, considered ideal internal standards, were used for the quantitation of indolamines. Because the angiotensin peptides are present in biological fluids at much lower concentrations than the previous two families of analytes, their analysis required the application of additional preconcentration techniques. In this work, the coupling of either of two types of electrophoretic preconcentration methods - field amplified injection (FAI) and isotachophoresis (ITP) - to capillary zone electrophoresis with both UV and MS detection was evaluated. Using FAI-CE-UV, angiotensins were detected at ~1 nM concentrations. Using similar conditions but TOFMS detection, the detection limits were below 10 nM. ITP was evaluated in both single-column and two-column comprehensive arrangements. The detection limits achieved for the ITP-based techniques were approximately one order of magnitude higher than for the FAI-based preconcentration. While the potential usefulness of these techniques was demonstrated using angiotensins standards, substantial additional research would be required to allow these approaches to be applied to plasma as part of clinical assays.
175

Paper Spray - Mass Spectrometry: Investigation of Sampling Devices for Illicit Drug Detection and Quantification

Chau Bao Nguyen (11178123) 06 August 2021 (has links)
Different sampling devices for paper spray - mass spectrometry (PS - MS) were investigated to improve the assay’s simplicity and sensitivity over traditional approaches. In the first one, pressure-sensitive adhesive paper was used as both sampling tool to collect drug residues on surfaces and paper substrate in PS - MS analysis. This method showed a significant improvement in drug collection on surfaces leading to low nano-gram level detection limits. Other sampling device being investigated was snap-in solid-phase extraction column, which demonstrated the ability to detect trace amounts of drugs in plasma while allowed easy transportation and the use of PS - MS automated system.
176

A Comparative Analysis of Per- andPolyfluoroalkyl Substances (PFAS) and ExtractableOrganofluorine (EOF) Using Solid PhaseExtraction-Weak Anion Exchange and Ion PairExtraction in SerumMarichal SalamehSpring 2021Independent project

Salameh, Marichal January 2021 (has links)
Per- and polyfluorinated substances (PFAS) are compounds that consist of a carbon chainbackbone that is partially or entirely fluorinated, with an addition of a functional group. SomePFAS are known as persistent organic pollutants (POPs) and have therefore been drawing a lot ofattention as well as increased concerns. PFAS have been detected in humans, wildlife and theenvironment and some have exhibited toxic effects such as hepatotoxicity, immunotoxicity,reproductive toxicity and endocrine disruption as well as being persistent and bioaccumulative.Serum, plasma and whole blood have been used as biomonitoring matrices in many studies toevaluate human exposure to PFAS. Restrictions have been applied to some PFAS, but thesecompounds are still ubiquitous. This study will investigate the performance (recovery, matrixeffect (ME) in terms of intra-/inter-day repeatability) of ion-pair extraction (IPE) and solid phaseextraction with weak anion exchange (SPE-WAX). The extraction methods were adapted fromliterature and 13 PFAS were selected for this work based on prior biomonitoring studies. Thetarget PFAS content was analyzed with liquid chromatography coupled with tandem massspectrometry (LC-MS/MS). The extraction methods were also compared for extractableorganofluorine (EOF) extraction in terms of blank levels as well as the amount extracted withdifferent methods; the EOF content was measured with combustion ion chromatography (CIC).The EOF levels were used to estimate the amount of unidentified organofluorine (UOF), to avoidunderestimating potential health hazards. Samples extracted using IPE had an average ionizationenhancement of 9%, while SPE-WAX showed an average ionization suppression of -1%. SPEWAXshowed higher average recoveries for procedural blanks (78%), horse serum (96%) andhuman serum (95%) in comparison to IPE (69%, 36%, 88%, respectively). The CIC analysis forEOF content was observed to be below MDL (<50 ng/mL F) with some contaminations observedin the procedural blanks.
177

Možnosti eliminace sulfonamidů z vodního ekosystému / Possibilities of elimination of sulfonamides from the aquatic ecosystem

Suková, Petra January 2018 (has links)
This diploma thesis focuses on the determination of sulfonamide antibiotics especially the possibility of elimination of these substances from the aquatic ecosystem. Nowadays, environmental contamination of the pharmaceuticals and their residues is a serious concern. Main sources of this contamination are wastewater treatment plants (WWTPs), where these compounds are not effectively removed by contemporary conventional technology. For this reason, new methods are being developed and tested that could eliminate the number of contaminants entering the environment in this way. There is a possibility to use the potential of the enzymatic system of wood-decay fungi, especially white rot fungi. Six representatives of sulfonamide antibiotics were selected and isolated from the aquatic matrix via solid phase extraction. The final identification and quantification method was high performance liquid chromatography with mass spectrometric detection. Monitoring of the concentration level of selected sulfonamide antibiotics at the inflow and effluent at the Brno-Modřice WWTP was carried out weekly. Moreover, the effectiveness of elimination of selected antibiotics from the aquatic ecosystem by the use of Trametes versicolor wood-decay fungi cultured on a suitable carrier was verified.
178

PROBIOTICKÉ GENY POTRAVINÁŘSKY VÝZNAMNÝCH BAKTERIÍ MLÉČNÉHO KVAŠENÍ / PROBIOTIC GENES OF SIGNIFICANT LACTIC ACID BACTERIA IN FOOD

Konečná, Jana Unknown Date (has links)
Isolation of deoxyribonucleic acid (DNA) is an important step in the molecular diagnostics of microorganisms. A high quality of isolated DNA is necessary for DNA amplification by the polymerase chain reaction (PCR). The conventional DNA isolation using phenol chloroform extraction and DNA precipitation in ethanol is time consuming and requires the use of toxic phenol. Magnetic separation techniques using magnetic solid particles are one of modern methods to speed up the nucleic acids isolation. The aim of this work was to use two different types of magnetic particles for solidphase DNA extraction. The amounts of DNA in separation mixtures were measured using ultraviolet spectrophotometry (UV). The first experimental conditions were tested on chicken erythrocytes DNA. Phosphate buffer (pH 7, 7.6 and 8) was used for adsorption of DNA on magnetic particles. It was shown that approximately almost one half of DNA was adsorbed to the particles. The elution conditions of DNA were also optimized. Secondly, bacterial DNA was tested. This DNA eluted from the particles was in PCR ready quality. High resolution melting (HRM) curve analysis is a simple, low-cost method for amplicon discrimination and easy connection with real-time polymerase chain reaction (PCR). In this contribution, we report rapid species identification of strains belonging to the Lactobacillus group using HRM-PCR. Three different DNA isolation methods were used in this work: phenol extraction, separation using magnetic particles and commercial kit. Ten sets of targeted gene fragments primers (LAC1 – LAC2, LAC2 – LAC4, P1V1 – P2V1, Gro F – Gro R, 3BA-338f – Primer 1, V1F – V1R, CHAU - V3F – CHAU - V3R, CHAU - V6F – CHAU - V6R, poxcDNAFw – poxPromRVC, poxcDNAFw – poxPromRVT) were tested for amplification of the 16S rRNA gene. Use of GroF/R and LAC2/4 primers pairs successfully identify strains belong to the Lactobacillus group. The variance between used extraction methods for evidence of HRM curves was found.
179

Využití molekulárně biologických technik pro identifikaci a analýzu probiotických bakterií / Use of Molecular Biology Techniques for Identification and Analysis of Probiotic Bacteria

Konečná, Jana January 2019 (has links)
Isolation of deoxyribonucleic acid (DNA) is an important step in the molecular diagnostics of microorganisms. A high quality of isolated DNA is necessary for DNA amplification by the polymerase chain reaction (PCR). The conventional DNA isolation using phenol-chloroform extraction and DNA precipitation in ethanol is time-consuming and requires the use of toxic phenol. Alternative method of DNA isolation is use of commercially available kits which, however, are expensive and their efficiency is low. Magnetic separation techniques using magnetic solid particles are one of modern methods to speed up the nucleic acids isolation. The aim of this work was to use two different types of magnetic particles for solid-phase DNA extraction. Magnetic microparticles P(HEMA – co – GMA) containing –NH2 group and nanoparticles PLL, whitch contains polylysine. The amounts of DNA in separation mixtures were measured using ultraviolet spectrophotometry (UV). The first experimental conditions were tested on chicken erythrocytes DNA. Phosphate buffer (pH 7, 7.6 and 8) was used for adsorption of DNA on magnetic particles. It was shown that approximately almost one half of DNA was adsorbed on the particles. The elution conditions of DNA were also optimized. Secondly, bacterial DNA was tested. After optimalization, the developed method was used for DNA isolation from real food supplements. This DNA eluted from the particles was in PCR ready quality. High resolution melting (HRM) curve analysis is a simple, low-cost method for amplicon discrimination and easy connection with real-time polymerase chain reaction (PCR). In this thesis, we report rapid species identification of strains belonging to the Lactobacillus group using HRM-PCR. Three different DNA isolation methods were used in this work: phenol extraction, separation using magnetic particles and commercial kit. Ten sets of targeted gene fragments primers (LAC1 – LAC2, LAC2 – LAC4, P1V1 – P2V1, Gro F – Gro R, 3BA-338f – Primer 1, V1F – V1R, CHAU - V3F – CHAU - V3R, CHAU - V6F – CHAU - V6R, poxcDNAFw – poxPromRVC, poxcDNAFw – poxPromRVT) were tested for amplification of the 16S rRNA gene. Use of GroF/R and LAC2/4 primers pairs successfully identify strains belong to the Lactobacillus group. The variance between used extraction methods for evidence of HRM curves was found.
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Stanovení nonylfenolu a jeho izomerů ve vodách / Determination of nonylphenol and its isomers in waters

Sedláček, Jaroslav January 2013 (has links)
This diploma thesis is focused on the issue of nonylphenol, degradation product of surfactants. Nonylphenol however most often arises in wastewater treatment plants predominantly during the microbial degradation of nonylphenol ethoxylates used in industry. It is a substance highly bioaccumulative, toxic predominantly to aquatic organisms. Furthermore, it belongs among hormone disruptors. The detailed research was prepared, on the basis which experimental part of diploma thesis was solved. Nonylphenol was determined in samples of the wastewater. The solid phase extraction (SPE) was used for the isolation of the analyte and purification of the extract. The final determination was performed on the gas chromatography with tandem mass spectrometry with time of flight analyzer (TOF). All steps of the preanalytical and the analytical procedure were optimized.

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