Development of on-line solid phase extraction using flow methods

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical chemistry Candidate: Bc. Jan Vinklárek Supervisor: doc. PharmDr. Petr Chocholouš, Ph.D. Title of the diploma thesis: Development of on-line solid phase extraction using flow methods The goal of this diploma thesis was to create and validate method using combination of SPE extraction and flow methods (in this case method SIA). Creatinine was chosen as extracted analyte and urine was chosen as biological material. At first, the method was optimized (concentration and flow rate of wash reagent and flow rate of sample and standards). Then the limits of the created method were tested. Finally, the trueness and repeatability of results was tested and also stability of diluted samples. All of these tests (in thesis named experiments) had good results. Final parameters of method are: Sorbent - SPH Iontosorb 100 Wash reagent - 50% acetonitrile, aspirated 0,5 ml Elute reagent - 1% water solution of ammonia hydroxide, aspirated 0,5 ml Sample diluted by acetic acid with pH 2,4, aspirated 20 µl, or 10 µl according to sample concentration (method alone makes decision about changing aspirated volume, decision algorithm is in the program) Method of standard adding is used for measuring creatinine concentration in...Univerzita Karlova v Praze Farmaceutická fakulta Katedra analytické chemie Kandidát: Bc. Jan Vinklárek Školitel: doc. PharmDr. Petr Chocholouš, Ph.D. Název diplomové práce: Vývoj metody on-line extrakce na tuhé fázi pomocí průtokových metod Cílem předložené diplomové práce bylo vyvinout a optimalizovat metodu využívající spojení extrakce na tuhé fázi a průtokových metod. Extrahovaným analytem byl zvolen kreatinin a biologickým materiálem moč. V prvním kroku se metoda nejprve optimalizovala (koncentrace a průtok promývacího činidla, průtok vzorku a standardu). Poté se testovala robustnost metody, a nakonec její správnost a opakovatelnost, dále se testovala i stabilita naředěných vzorků. Všechny tyto testy dopadly dobře a podařilo se metodu optimalizovat. Finální parametry metody jsou následující: Sorbent - SPH Iontosorb 100 Promývací činidlo - 50% acetonitril, nasáváno 0,5 ml Eluční činidlo - 1% vodný roztok hydroxidu amonného, nasáváno 0,5 ml Vzorek ředěný kyselinou octovou o pH 2,4, nasáváno 20 µl, nebo 10 µl podle koncentrace vzorku (rozhodnutí o změně nasávaného objemu metoda provede sama, v programu je rozhodovací algoritmus) Pro zjištění koncentrace vzorku je používaná metoda standardního přídavku. Používá se standard o koncentraci 2mg/l v nástřicích 0, 10, 20 µl. Vzorky se měří v...Katedra analytické chemieDepartment of Analytical ChemistryFaculty of Pharmacy in Hradec KrálovéFarmaceutická fakulta v Hradci Králov

Case report: Susac syndrome—two ends of the spectrum, single center case reports and review of the literature

Susac syndrome is a rare and enigmatic complex neurological disorder primarily affecting small blood vessels in the brain, retina, and inner ear. Diagnosing Susac syndrome may be extremely challenging not only due to its rarity, but also due to the variability of its clinical presentation. This paper describes two vastly different cases—one with mild symptoms and good response to therapy, the other with severe, complicated course, relapses and long-term sequelae despite multiple therapeutic interventions. Building upon the available guidelines, we highlight the utility of black blood MRI in this disease and provide a comprehensive review of available clinical experience in clinical presentation, diagnosis and therapy of this disease. Despite its rarity, the awareness of Susac syndrome may be of uttermost importance since it ultimately is a treatable condition. If diagnosed in a timely manner, early intervention can substantially improve the outcomes of our patients

Development of on-line solid phase extraction using flow methods

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical chemistry Candidate: Bc. Jan Vinklárek Supervisor: doc. PharmDr. Petr Chocholouš, Ph.D. Title of the diploma thesis: Development of on-line solid phase extraction using flow methods The goal of this diploma thesis was to create and validate method using combination of SPE extraction and flow methods (in this case method SIA). Creatinine was chosen as extracted analyte and urine was chosen as biological material. At first, the method was optimized (concentration and flow rate of wash reagent and flow rate of sample and standards). Then the limits of the created method were tested. Finally, the trueness and repeatability of results was tested and also stability of diluted samples. All of these tests (in thesis named experiments) had good results. Final parameters of method are: Sorbent - SPH Iontosorb 100 Wash reagent - 50% acetonitrile, aspirated 0,5 ml Elute reagent - 1% water solution of ammonia hydroxide, aspirated 0,5 ml Sample diluted by acetic acid with pH 2,4, aspirated 20 µl, or 10 µl according to sample concentration (method alone makes decision about changing aspirated volume, decision algorithm is in the program) Method of standard adding is used for measuring creatinine concentration in..

Incidence of Lyme disease pathogens in ticks

V této práci se zabývám výskytem infikovaných klíšťat v Plzeňském kraji. Z výsledků vyplývá, že infikovaná klíšťata se nacházejí na všech zvolených lokalitách a procento infikovanosti nevybočuje z celorepublikového průměru.ObhájenoIn this thesis is monitored incidence of infected ticks in Pilsen Region. Results are saying that infected ticks are localed in every selected localites and percents of infectected ticks are in republic's average

Chemické zasychání alkydových pryskyřic katalyzované benzoylferrocenem

Catalytic properties of benzoylferrocene, as a representative of cobalt-free drier, was investigated on alkyd resin modified with soybean oil. Mechanical tests, performed on alkyd films, revealed promising activity at low metal concentrations. A detailed analysis of time resolved infrared spectra was used for in-depth investigation of chemical curing in the films. The experiments, performed in transmission mode, enabled determination of kinetic parameters for the autoxidation process. Effects of film thickness were investigated using attenuated total reflectance technique.Katalytické vlastnosti benzoylferrocenu byly studovány na alkydové pryskyřici modifikované sojovým olejem. Mechanické testy na zkušebních nátěrech ukázaly aktivitu při nízkých koncentracích kovu. Podrobná analýza infračervených spekter s časovým rozlišením umožnila získání kinetických parametrů a vlivu tloušťky nátěru na prosychání filmů

Vliv primárních sikativů na zasychání vysokosušinových alkydových pojiv.

Catalytic activity of four primary driers was investigated in high-solid alkyd binder modified with tall oil fatty acids. The drying activity was established by mechanical tests. Infrared spectroscopy was used for detailed investigation of chemical changes during the autoxidation process. Due to strong thickness effect, the infrared study was performed using attenuated total reflectance (ATR) technique, which measures spectra of a thin layer from the interface sample/ATR crystal (down surface of the sample). Coatings of 30-wet thickness were found to be enough thin to be considered as a homogenously dried bulk with negligible effect of oxygen diffusion. It makes the 30-layers very suitable for determination of kinetic parameters of the autoxidation process. For the first time, ATR-IR experiments on several samples of the same composition but different film thickness were used for detailed investigation of the thickness effect.Katalytická aktivita čtyř primárních sikativů byla studována ve vysokosušinových alkydových pojivech modifikovaných mastnými kyselinami talového oleje. Sikativační aktivita byla určena mechanickými zkouškami. Infračervená spektroskopie byla použita pro podrobné studium chemických procesů probíhajících při zasychání. Tato studie byla provedena za pomocí ATR techniky, která umožňuje získat spektra z tenké vrstvy na rozhraní vzorek/ATR krystal. Vrstvy 30-mokré tloušťky byly dostatečně tenké pro získání kinetických parametrů autooxidačního procesu. Série vzorků stejného složení s různou tloušťkou byly použity pro podrobné studium prosychání nátěru

Hydrolýza vanadocen dichloridu

A key hydrolysis product of vanadocene dichloride was isolated and structurally characterized. The oligomeric character of the species precludes its detection by classical EPR spectroscopic tools. A detailed study of the with high purity reagents disproves appearance of Cp2V(OH)2, which was postulated previously based on mechanistic approach.Klíčový produkt hydrolýzy vanadocendichloridu byl izolován a strukturně charakterizován. Oligomerní charakter této částice neumožňuje její detekci pomocí EPR spektroskopie. Podrobná studie vyloučila možnost vzniku dríve postulovaného komplexu Cp2V(OH)2

Sikativační aktivita 2-ethylhexanoatu oxovanadičitého v alkydových nátěrových hmotách

Oxovanadium(IV) 2-ethylhexanoate was established as a new primary drier for alkyd-based paints. A series of experiments has demonstrated an excellent drying activity toward solvent-borne alkyd resins of different oil length at considerably lower metal concentration than optimal for commercial cobalt(II) 2-ethylhexanoate. The behavior in real paint was simulated on formulations bearing inhibitor of autooxidation. The detailed studies of the drying process have shown that the relatively slow initial step of autooxidation reaction, when compared with cobalt compounds, is compensated for by the absence of the induction times. Furthermore, the active oxovanadium(IV) species are not consumed during the drying processes as evidenced by EPR spectroscopic measurements.2-ethylhexanoatu oxovanadičitý vykazuje vlastnosti typické pro primární sikativy. Uvedené experimenty ukazují výbonou sikativační aktivitu vůči alkydovým pryskyřicím různé olejové délky při výrazně nižších koncentracích než je běžné u komerčních 2-ethylhexanoatu kobaltnatého. Chování v reáné formulaci bylo simulováno na sysytémech s inhibitory autooxidace

Oxovanadium(IV) 2-etylhexanoát jako sikativ pro rozpouštědlové alkydové pryskyřice

Air-drying binders are well-established paints used in modern organic coating technologies. Alkyd resins modified with polyunsaturated fatty acids (e.g. linoleic acid, linolenic acid) are able to provide polymeric film without addition of any curing agents but this process is generally very slow. Therefore, the use of catalysts, socalled driers, is necessary for acceleration of the drying process and improvement of the physical properties of resulting polymeric film. This work was focused on the drying properties of oxovanadium(IV) 2-ethylhexanoate in the different solvent-borne alkyd binder. The several experimental methods as a film drying time, surface hardness determined by pendulum Persoz were used for determining drying activity of oxovanadium(IV) 2-ethylhexanoate. These experiments demonstrated an excellent drying activity for solvent-borne alkyd resin. Oxovanadium(IV) 2-ethylhexanoate exhibited great drying activity at considerably lower concentration than the commercial dryer cobalt(II) 2-etylhexanoate.Tato práce je zaměřena na sikativační aktivitu oxovanadium(IV) 2-ethylhexanoatu v různých alkydových pojivech. Pro určení aktivity tohoto komplexu bylo použito několik experimentálních metod jako jsou měření doby zasychání zkušebních filmů a měření relativní tvrdosti těchto filmů pomocí kyvadla Persoz. Tyto experimenty potvrdily velice dobré sikativační vlastnosti komplexu v alkydech různé olejové délky