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Further characterization of the direct injection nebulizer for flow injection analysis and liquid chromatography with inductively coupled plasma spectrometric detectionAvery, Thomas W. January 1988 (has links)
A direct injection nebulizer (DIN) was constructed in our laboratory and was evaluated as an interface between a liquid chromatography column and an inductively coupled plasma-atomic emission spectrometer (ICP-AES). Optimum operating conditions, detection limits and reproducibility of the DIN closely matched literature data for a somewhat different commercial device. In addition, when using the DIN for sample introduction, the ICP detection exhibited uniform response towards phosphorous compounds of different volatilities. / Department of Chemistry
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Molekulargenetische Diagnostik des ATRX-Syndroms mittels Denaturing High-Performance Liquid Chromatography (DHPLC)Junge, Cornelia 07 July 2014 (has links) (PDF)
Die DNA-Sequenzierung nimmt in der molekulargenetischen Diagnostik seit vielen Jahren einen großen Stellenwert ein. Zeit- und kosteneffektivere Methoden wie die DHPLC wurden seither für verschiedene Gene etabliert. Ziel dieser Arbeit war die Etablierung der DHPLC für das ATRX-Gen bei Patienten mit Verdacht auf das ATRX-Syndrom. Nach erfolgreicher Etablierung der DHPLC sollten im Rahmen dieser Arbeit 38 Patientenproben des Instituts für Humangenetik der Universität Leipzig mit Verdacht auf das ATRX-Syndrom mittels DHPLC und Sequenzierung untersucht werden.
Die Etablierung der DHPLC gelang in der vorliegenden Arbeit für alle - das ATRX-Gen vollständig umspannenden - 42 Fragmente. Jede der vorliegenden Sequenzvariationen konnte nach Abschluss der Arbeit detektiert werden. Unter Verwendung von Maxima® stellten sich initial 22 von 24 verschiedenen Sequenzvariationen zum Wildtyp different dar. Die verbleibenden zwei Mutationen p.R246C und p.A238P im Fragment 9 wurden unter Verwendung höherer Temperaturen, eines kürzeren Fragmentes oder anderer Polymeraseenzyme (AmpliTaq Gold® bzw. HighFidelity) detektiert. Nach Abschluss der Etablierung der DHPLC konnte eine Sensitivität und Spezifität von 100% erreicht werden.
In den Patientenuntersuchungen des Instituts für Humangenetik der Universität Leipzig fanden sich bei 38 Patientenproben vier verschiedene als benigne beschriebene Polymorphismen bei insgesamt 19 Patienten, ein noch nicht veröffentlichter Polymorphismus im Intron 26 sowie eine bis dato nicht beschriebene und als pathogen einzustufende Mutation im Exon 34. In 100 Kontrollen der DNA-Bank des Instituts für Humangenetik der Universität Leipzig konnte der bisher nicht publizierte Polymorphismus im Intron 26 sieben Mal gefunden werden. Die bis dato nicht beschriebene Deletion p.2385_2395del im Exon 34 führt zu einem vorzeitigen Abbruch des ATRX-Proteins und ist somit als sicher pathogen einzustufen. Die Untersuchung der Mutter des Patienten konnte den Konduktorenstatus nachweisen. Für die Familie des betroffenen Patienten konnte mit der vorliegenden Arbeit die Diagnose des ATRX-Syndroms gesichert werden.
Die DNA-Proben der Patienten bei denen keine Mutation nachgewiesen werden konnte, sollten bei weiterhin dringendem Verdacht auf das ATRX-Syndrom mittels qRT-PCR bzw. MLPA untersucht werden, um große Deletionen, Insertionen oder Duplikationen auszuschließen.
Mithilfe dieser Arbeit gelang die Etablierung der DHPLC für das ATRX-Gen als ökonomische, sehr sensitive und effiziente Methode zur Diagnostik des ATRX-Syndroms. Die Entscheidung, in welcher Form und mit welcher Methode DNA-Proben bei Verdacht auf ATRX-Syndrom untersucht werden, bleibt jedoch eine individuelle Entscheidung jedes Instituts unter Betrachtung der jeweiligen Gegebenheiten vor Ort.
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„Polifenolinių rūgščių įvertinimas rykštenės (Solidago L.) augalinėje žaliavoje“ / Analysis of polyphenolic acids belonging to goldenrod (Solidago L.) speciesKamandulytė, Simona 18 June 2014 (has links)
Rykštenė yra daugiametis augalas, priklausantis astrinių šeimai. Ji pasižymi keliais farmakologiniais veikimais, tokiais kaip skatinančiu diurezę, priešuždegiminiu, analgetiniu, antispazmolitiniu, antibakteriniu ir antigrybeliniu, taip pat antioksidaciniu ir priešvėžiniu aktyvumu. Iš rykštenės žaliavos gaminami vaistai skatinantys diurezę. Ji taip pat įeina į Lietuvoje gaminamos arbatos „Diuretiko“ (UAB „Acorus Calamus”) sudėtį. Šio darbo tikslas - atlikti polifenolinių rūgščių kokybinę ir kiekybinę analizę rykštenės ekstraktuose taikant efektyviąją skysčių chromatografiją. Buvo paruošti Solidago virgaurea ir Solidago gigantea lapų ir žiedų ekstraktai naudojant vandeninį metanolio tirpalą (70%). Jie buvo analizuojami ESC metodu. Detekcijai naudojamas fotodiodų matricos detektorius. Gauti rezultatai buvo lyginami su standartinių junginių (chlorogeno ir neochlorogeno rūgščių) duomenimis. Polifenolinės rūgštys nustatomos bangos ilgiui esant 324nm. Buvo identifikuotos dvi polifenolinės rūgštys: chlorogeno ir neochlorogeno. Solidago virgaurea chlorageno rūgšties yra 1.31%, o neochlorogeno rūgšties – 0.06%. Solidago gigantea chlorogeno rūgšties procentinis kiekis yra 2.35%, o neochlorageno rūgšties – 0.02%. / Goldenrod is a perennial plant belonging to the Asteraceae family. It has several pharmacological functions, such as promoting diuresis, anti-inflammatory, analgesic, antispazmolitiniu, antibacterial and antifungal as well as anti-oxidative and anti-tumor activity. Of goldenrod made a medicaments stimulating diuresis. It also includes in production of tea „Diuretiko“ (UAB „Acorus Calamus”) composition in Lithuanian. The aim of this research was to make polyphenolic acids qualitative and quantitative analysis of the goldenrod extracts using high-performance liquid chromatography. Was prepared Solidago virgaurea and Solidago gigantea leaves and flowers extracts of aqueous methanol (70%). They were analyzed in HPLC method. For detection was used photodiode array detector. The results were compared with standard compounds (chlorogenic and neochlorogenic acids) data. Polyphenolic acids determined at the wave length of 324nm. Has been identified two polyphenolic acids: chlorogenic and neochlorogenic. In Solidago virgaurea chlorogenic acid is 1.31% and neochlorogenic acid - 0.06%. In Solidago gigantea chlorogenic acid percentage is 2.35%, and neochlorogenic acid - 0.02%.
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Vitamino E preparatų analizė efektyviosios skysčių chromatografijos metodu / The analysis of food supplements containing vitamin E using high performance liquid chromatographyKirjanovas, Mindaugas 18 June 2014 (has links)
Nuolatos plečiantis maisto papildų rinkai ir augant naujai sukuriamų papildų kiekiui būtina sukurti greitas, tikslias ir efektyvias papildų analizės metodikas, norint užtikrinti į rinką tiekiamų farmacinių prepartų kokybę. Vitamino E nustatymui efektyviosios skysčių chromatografijos būdu yra sukurta nemažai įvairių metodikų, tačiau svarbu žinoti, kuri metodika yra efektyviausia būtent vitamino E preparatams.
Tyrimo tikslas - atlikti kokybinį ir kiekybinį tokoferolio acetato nustatymą pritaikant efektyviosios skysčių chromatografijos metodą bei surasti efektyviausią tokoferolio acetato ekstrakcijos metodiką vaistinių preparatų analizei.
Tyrimo uždaviniai - surinkti ir apibendrinti informaciją apie vitaminą E, jo poveikį organizmui, maisto papildus su tokoferolio acetatu bei jų analizę; optimizuoti metodiką tokoferolio acetato preparatų analizei efektyviosios skysčių chromatografijos būdu ir ją validuoti; atlikti tokoferolio acetato preparatų (maisto papildo ir vaistinio preparato) paruošimą analizei įvairiomis ekstrakcijos metodikomis; išanalizuoti gautus duomenis ir padaryti išvadas apie efektyviausias ekstrakcijos metodikas bandinių paruošimui bei skirtumus tarp vaistinio preparato ir maisto papildo analizės.
Metodas – tyrimas atliktas chromatografine sistema su fotodiodų matricos detektoriumi. Mobilioji fazė – metanolis:distiliuotas vanduo (95:5), tekėjimo greitis – 1.2 ml/min, bandinio tūris – 10 µl, trukmė – 14 min, bangos ilgis – 282 nm. Išbandytos preparatų... [toliau žr. visą tekstą] / The food supplements market is constantly growing and new products are entering it everyday. In order to assure the quality of these pharmaceuticals it is important to develop methods of analysis which are fast, precise and effective. There are many methods created for the analysis of vitamin E using high-performance liquid chromatography so it is important to know which of them are the most effective for vitamin E food supplements.
The aim – to perform a qualitative and a quantitive assey of tochopherol acetate using high performance liquid chromatography and to find the most effective method of extracting tocopherol acetate from food suplements.
The tasks – to collect and to summarize the data on vitamin E, its effects on human body, on the supplements containing tocopherol acetate and their analysis; to develop a high-performance liquid chromatography method of analysis suitable for the pharmaceuticals containing tocopherol acetate ant to validate it; to perform a tocopherol acetate (a food supplement and a drug) samples preparation using different techniques chosen; to analyze the data collected and to make conclusions about the most effective way of preparing samples for the analysis and about the differences between a drug and a food supplement analysis.
The method – the study was conducted by high-performance liquid chromatography using a photodiode matrix detector. Mobile phase – methanol:purified water (95:5), flow-rate – 1.2 ml/min, injection volume – 10 µl... [to full text]
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Fenolinių junginių kokybinės ir kiekybinės sudėties įvairavimo šermukšnių (S. aucuparia l.) lapuose ir žieduose tyrimas / Qualitative and quantitative study of phenolic compounds variation in S.aucuparia L. leaves and flowersVaitūnaitytė, Malvina 30 June 2014 (has links)
Tyrimo objektas ir metodai: Sorbus L. genties augalo S. aucuparia L. lapų ir žiedų tyrimas. Bendras fenolinių junginių kiekis paprastojo šermukšnio augalinėse žaliavose nustatytas UV spektrofotometriniu metodu, fenolinės rūgštys ir flavonoidai nustatyti ESC metodu.
Darbo tikslas: nustatyti S. aucuparia L. lapuose ir žieduose esančius fenolinius junginius, jų kiekinės sudėties įvairavimą augalo vegetacijos metu ir augalinių žaliavų (lapų ir žiedų) laikymo metu.
Darbo uždaviniai: Surinkti ir susisteminti literatūros duomenis apie Sorbus aucuparia L., paprastojo šermukšnio augalinių žaliavų cheminę sudėtį, fenolinių junginių analizės metodus, poveikį ir panaudojimą medicinos praktikoje; Ištirti S. aucuparia L. lapų ir žiedų kiekybinę fenolinių junginių sudėtį ir nustatyti bendro fenolinių junginių kiekio įvairavimą augalo vegetacijos metu; Ištirti S. aucuparia L. lapų ir žiedų kokybinę ir kiekybinę fenolinių rūgščių ir flavonoidų sudėtį ir nustatyti jų kiekinės sudėties kitimą augalų vegetacijos periodo metu; Nustatyti S. aucuparia L. lapuose ir žieduose esančių fenolinių junginių kiekybinės sudėties kitimus augalinių žaliavų laikymo metu.
Išvados: S. aucuparia L. augalinės žaliavos gali būti kaip šaltinis išskiriant biologiškai aktyvius junginius, kurie gali būti naudojami medicinos praktikoje. S. aucuparia L. lapuose ir žieduose esančių junginių kiekis kinta augalo vegetacijos metu; lapuose daugiausia fenolinių junginių sukaupiama gegužės - birželio mėn., žieduose – žydėjimo... [toliau žr. visą tekstą] / Object and methods: Sorbus aucuparia L. leaves and flowers study. Total amaunt of phenolic compounds in mountain ash leaves and flowers were evaluated using UV spectrophotometry, phenolic acids and flavonoids were identified and evaluated using HPLC.
Aim: to identify and evaluate the content of phenolic compounds in rowan leaves and flowers during mountain ash vegetation and during plant materials (leaves and flowers) storage.
Objective: to collect and organise the information about the use of Sorbus aucuparia L., S. aucuparia L. leaves and flowers acumulated compounds, phenolic compounds analysis methods and the impact of the use in medical practice; to perform quantitative analysis of S. aucuparia L. leaves and flowers phenolic compounds and to determine the total phenolics content during rowan growing season; to perform qualitative and quantitative analysis of S. aucuparia L. leaves and flowers phenolic acids and flavonoids and to determine the variation of the phenolics content during rowan growing season; to determine phenolic compounds content changes in Sorbus aucuparia L. plant materials (flowers and leaves) during them storage.
Conclusions: S. aucuparia L. leaves and flower is a source of biological active substances which can be used in medicinal practice. Phenolic compounds content in S. aucuparia L. leaves and flowers change during vegetation; mainly phenolic compounds in leaves was accumulated in May - June, in flowers - in the beginning of flowering and massive... [to full text]
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Structural Characterization of Freshwater Dissolved Organic Matter from Arctic and Temperate Climates Using Novel Analytical ApproachesWoods, Gwen 19 March 2013 (has links)
Dissolved organic matter (DOM) is comprised of a complex array of molecular constituents that are linked to many globally-relevant processes and yet this material is still largely molecularly uncharacterized. Research presented here attempted to probe the molecular complexity of this material from both Arctic and temperate climates via multifaceted and novel approaches. DOM collected from remote Arctic watersheds provided evidence to suggest that permafrost-disturbed systems contain more photochemically- and biologically-labile material than undisturbed systems. These results have large implications for predicted increasing temperatures where widespread permafrost melt would significantly impact stores of organic carbon in polar environments. In attempting to address the complexities and reactivity of DOM within global environments, more information at the molecular-level is necessary. Further research sought to unravel the molecularly uncharacterized fraction via use of nuclear magnetic resonance (NMR) spectroscopy in conjunction with hyphenated and varied analytical techniques. Directly hyphenated high performance size exclusion chromatography (HPSEC) with NMR was explored. This hyphenation was found to separate DOM into structurally distinct fractions but proved limited at reducing DOM heterogeneity. Of the many high performance liquid chromatography (HPLC) techniques tested, hydrophilic interaction chromatography (HILIC) was found the most effective at simplifying DOM. HILIC separations utilizing a sample from Florida resulted in fractions with highly resolved NMR signals and substantial reduction in heterogeneity. Further development with a 2D-HILIC/HILIC system to achieve additional fractionation was employed. This method produced fractions of DOM that were homogenous enough to produce excellent resolution and spectral dispersion, permitting 2D and 3D NMR experiments to be performed. Extensive NMR analyses of these fractions demonstrated strong evidence for the presence of highly oxidized sterols. All fractions, however, provided 2D NMR spectra consistent with oxidized polycyclic structures and support emerging data and hypotheses suggesting that cyclic structures, likely derived from terpenoids, are an abundant, refractory and major component of DOM. Research presented within this thesis demonstrates that HILIC and NMR are excellent co-techniques for the analysis of DOM as well as that oxidized sterols and other cyclic components with significant hydroxyl and carboxyl substituents are major constituents in DOM.
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Development of analytical methods for the speciation of arsenic in the marine environmentMomplaisir, Georges-Marie January 1995 (has links)
Several biologically important arsenic compounds including methylarsonate, trimethylarsine oxide, tetramethylarsonium ion, arsenobetaine and arsenocholine were prepared, in good yields, from sodium arsenite, or dimethylarsinic acid. These organoarsenic compounds together with arsenite, arsenate and dimethylarsinic acid were used as standards for the development of analytical methods for determining the levels of individual arsenic compounds (arsenic speciation) present in natural matrices. / Arsenobetaine, arsenocholine and tetramethylarsonium ion were separated by high performance liquid chromatography (HPLC) with on-line detection by thermochemical hydride generation (THG)-AAS. The analytes were eluted from the cyanopropyl bonded phase HPLC column with a 1% acetic acid methanolic mobile phase which also contained diethyl ether triethylamine, and trimethylsulfonium iodide or picrylsulfonic acid. A surface response methodology and a univariate optimization procedure were used to determine the optimum concentration of solvent modifiers in the methanolic mobile phase. Limits of detection in the range 4-5 ng (as As) were obtained for the arsonium analytes under optimum chromatographic conditions. / A simple phenol extraction procedure was developed to isolate arsonium analytes from edible marine tissues (lobster tail muscle, peeled and deveined shrimp, and cod fillet), cod liver oil and human urine. The crude extracts were separated on the cyanopropyl column using a methanolic mobile phase and detected on-line by THG-AAS. Recoveries from tissues or from urine which had been spiked at 0.1-3.4 $ mu$g of As cation/g of fresh weight were 80% or greater for each of five sample types. / An improved HPLC-AAS interface which was compatible with either aqueous or organic mobile phases was also developed. The interface provided approximately equivalent responses to different arsenic oxidation states which resulted in low to subnanogram chromatographic limits of detection for arsenic oxyanions and arsonium cations in an aqueous or methanolic mobile phase. Nascent As anions and As cations were conveniently coextracted from aqueous solution or from fish muscle by phenol extraction and quantified in the same chromatographic run. This method has been applied to a standard reference sample of dogfish muscle (DORM-1), a marine reference sediment sample (PACS-1) and to sediment porewaters (SAG-15) from the Saguenay Fjord.
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Method development in electrospray ionisation fourier transform ion cyclotron resonance mass spectrometry study of plant oils - macadamia oil as a modelMokhtari-Fard, Ahmad, Chemistry, Faculty of Science, UNSW January 2008 (has links)
A novel analytical method is developed to examine the chemical composition of plant oils by electrospray ionisation high-resolution Fourier transform ion cyclotron resonance mass spectrometry in both positive- and negative-ion modes. To date, this is the first reported application of this technique for the study of macadamia nut oil. Samples of macadamia nut oil from the Macadamia Integrifolia- Proteaceae family (smooth shell) are examined. The fatty acid profile of the oil is obtained by this mass spectrometric examination of the transesterified and hydrolysed oil samples. The Fourier transform ion-cyclotron resonance mass spectrometry results are compared to those obtained from similar samples using gas chromatography-mass spectrometry techniques. High performance liquid chromatography and Fourier transform ion cyclotron resonance mass spectrometry are used to separate and assign the isomers present in the methanol extract of the oils in separate experiments. Significant results in this study include: - The first observation and identity of a number of oxidised triacylglycerols in macadamia oil samples. - The first observation of oxidised and free fatty acids, measured directly in hydrolysed oil and in the methanol extract of macadamia oil. - High resolution Fourier transform ion cyclotron resonance mass spectrometry in broadband mode which enables isobars to be observed. - Esterified oil Fourier transform ion cyclotron resonance mass spectrometry results are consistent with our gas chromatography-mass spectrometry results and with the results of similar studies on macadamia oil in the literature. - A number of fatty acids with odd number of carbon atoms are observed in the oil. - In electrospray ionisation Fourier transform ion cyclotron resonance mass spectrometry of oils, the sample preparation is straightforward. The sample is dissolved in methanol or acetonitrile and the solution is introduced to the electrospray source directly. Introducing oil samples to the gas chromatograph-mass spectrometer needs the oils to be esterified prior to the analysis. - In this work, state-of-the-art mass spectrometry demonstrates distinct advantages in comparison to gas chromatography measurements such as direct identification of free fatty acids in oil samples, whereas this is not possible in gas chromatography-mass spectrometry due to the required esterification step prior to the analysis. - High performance liquid chromatography fraction collection is combined with Fourier transform ion cyclotron resonance mass spectrometry in off-line mode and found to improve the sensitivity, selectivity and signal to noise levels due to the lower number of compounds in each high performance liquid chromatography fraction compared to the methanol extract of macadamia oil sample. Also isomers of monoacylglycerols have been resolved using the high performance liquid chromatography technique.
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High-performance liquid chromatography analysis of fatty acids and mathematical modeling of liquid chromatographyLi, Zhiguo. January 2001 (has links)
Thesis (Ph. D.)--Ohio University, March, 2001. / Title from PDF t.p.
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Hyphenated HPLC-MS technique for analysis of compositional monosaccharides of transgenic corn glycoprotein and characterization of degradation products of diazinon, fonofos and aldicarb in various oxidation systemsWang, Tongwen, January 2007 (has links) (PDF)
Thesis (Ph. D.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 23, 2008) Includes bibliographical references.
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