Advanced search

Showing result 1 - 5 of 243 swedish dissertations matching the above criteria.

  2. 1. Selectivity in NMR and LC-MS Metabolomics : The Importance of Sample Preparation and Separation, and how to Measure Selectivity in LC-MS Metabolomics

    Author : Albert Elmsjö; Curt Pettersson; Torbjörn Arvidsson; Thomas Moritz; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Metabolomics; NMR; LC-MS; HILIC; UHPLC; Q-ToF; selectivity; co-feature ratio; method evaluation; data evaluation; Analytical Pharmaceutical Chemistry; Analytisk farmaceutisk kemi;

    Abstract : Until now, most metabolomics protocols have been optimized towards high sample throughput and high metabolite coverage, parameters considered to be highly important for identifying influenced biological pathways and to generate as many potential biomarkers as possible. From an analytical point of view this can be troubling, as neither sample throughput nor the number of signals relates to actual quality of the detected signals/metabolites. READ MORE

  4. 2. Damsel in distress – metabolomics as a novel tool to investigate the effects of wastewater exposure on damselfly larvae

    Author : Jana Späth; Malin L. Nording; Jerker Fick; Stina Jansson; Tuulia Hyötyläinen; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; biomarkers; ecotoxicology; invertebrates; GC-MS; LC-MS; LC-MS MS; metabolomics; micropollutants; pharmaceuticals; risk assessment; ekotoxikologi; Ecotoxicology; Analytical Chemistry; analytisk kemi;

    Abstract : Aquatic organisms, such as aquatic invertebrates, are exposed to anthropogenic pollutants through their environment. These pollutants, despite their low levels, can adversely affect exposed individuals or even entire ecosystems, especially when present in complex mixtures. READ MORE

  5. 3. Development of analytical methods for the determination of the small molecule component of complex biological systems

    Author : Kristian Pirttilä; Mikael Hedeland; Curt Pettersson; Torbjörn Arvidsson; Thomas Moritz; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; metabolomics; data processing; peak characterization; algorithm; multivariate data analysis; chromatography; sequential columns; HILIC; RPLC; liquid chromatography; mass spectrometry; LC; MS; noise-induced hearing loss; NIHL; guinea pig; perilymph; method development; validation; R; C ; Analytical Pharmaceutical Chemistry; Analytisk farmaceutisk kemi;

    Abstract : The research field of untargeted metabolomics aims to determine the relative abundance of all small metabolites in a biological system in order to find biomarkers or make biological inference with regards to the internal or external stimuli. This is no trivial aim, as the small metabolites are both vast in numbers and extremely diverse in their chemical properties. READ MORE

  6. 4. Diagnosis of acute and chronic enteric fever using metabolomics

    Author : Elin Näsström; Henrik Antti; Anders Johansson; Peter Spégel; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Enteric fever; Salmonella; chronic carriers; metabolomics; diagnosis; biomarkers; multivariate data analysis; GCxGC-MS; GC-MS; LC-MS;

    Abstract : Enteric (or typhoid) fever is a systemic infection mainly caused by Salmonella Typhi and Salmonella Paratyphi A. The disease is common in areas with poor water quality and insufficient sanitation. Humans are the only reservoir for transmission of the disease. READ MORE

  7. 5. Novel Solid Phase Extraction and Mass Spectrometry Approaches to Multicomponent Analyses in Complex Matrices

    Author : Nahid Amini; Gunnar Thorsén; Tuulia Hyötyläinen; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Sample preparation; SPE; RAM; GCB µ-trap; GCB disk; High temperature LC; LC MS; ESI; APCI; Matrix effects; LIT-MS; SALDI; Sample screening; Oxidized GCB; Silicon nitride; Analytical chemistry; Analytisk kemi; Analytical Chemistry; analytisk kemi;

    Abstract : Analysis of compounds present in complex matrices is always a challenge, which can be partly overcome by applying various sample preparation techniques prior to detection. Ideally, the extraction techniques should be as selective as possible, to minimize the concentration of interfering substances. READ MORE