Search for dissertations about: "electrospray"

Showing result 1 - 5 of 151 swedish dissertations containing the word electrospray.

2. 1. Development of Sheathless Electrospray Mass Spectrometry and Investigations of Associated Electrochemical Processes – A Fairy Tale

   Author : Stefan Nilsson; Karin Markides; Leif Nyholm; Jonas Bergquist; Per Andrén; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Analytical chemistry; electrospray; sheathless; mass spectrometry; capillary electrophoresis; electrochemistry; chromatography; interface; fairy dust; gold; Analytisk kemi; Analytical chemistry; Analytisk kemi;

   Abstract : In microscale separations, such as capillary electrophoresis and -liquid chromatography, the liquid flow rates are in the order of nanoliters per second. If such flow rates are to be interfaced with a mass spectrometer (MS) using electrospray (ES) ionization, without loss of separation efficiency, each fraction of the analyte zone must remain undisturbed by the high voltage contact necessary for ES. READ MORE

4. 2. Mass Spectrometry with Electrospray Ionization from an Adjustable Gap

   Author : Patrik Ek; Åsa Emmer; Johan Roeraade; Per M. Claesson; Ulrika Nilsson; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Electrospray ionization; mass spectrometry; nanoelectrospray; ESI; MS; chip; emitter; gap; liquid bridge; nozzle; peptides; Analytical chemistry; Analytisk kemi;

   Abstract : In this thesis the fabrication and analytical evaluation of two new electrospray emitters utilized for mass spectrometry analysis is presented. The emitters are based on a new concept, where the spray orifice can be varied in size. The thesis is based on two papers. All present-day nanoelectrospray emitters have fixed dimensions. READ MORE

5. 3. Aspects of Porous Graphitic Carbon as Packing Material in Capillary Liquid Chromatography

   Author : Anna Törnkvist; Wolfgang Lindner; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Analytical chemistry; PGC; porous graphitic carbon; stationary phase; packing material; LC; liquid chromatography; miniaturized; chiral; enantiomer; ESI; electrospray ionization; mass spectrometry; polar compounds; L-DOPA; dopamine; biological samples; biological matrix; Analytisk kemi; PGC; poröst grafitiserat kol; stationärfas; packningsmaterial; LC; vätskekromatografi; miniatyriserade system; kiral; enantiomer; ESI; electrospray jonisation; mass spektrometri; polära föreningar; L-DOPA; dopmamine; biologiska prover; biologisk matris; Analytical chemistry; Analytisk kemi; Analytical Chemistry; Analytisk kemi;

   Abstract : In this thesis, porous graphitic carbon (PGC) has been used as packing material in packed capillary liquid chromatography. The unique chromatographic properties of PGC has been studied in some detail and applied to different analytical challenges using both electrospray ionization-mass spectrometry (ESI-MS) and ultra violet (UV) absorbance detection. READ MORE

6. 4. Development of methods for determining aflatoxins in biological material

   Author : Anders Kussak; Rainer Stephany; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Aflatoxins; Mycotoxins; Carcinogen; Airborne dust; Urine; Feed factories; Immunoaffinity extraction; Solid-phase extraction; Post-column derivatization; Electrospray; Mass spectrometry;

   Abstract : In this thesis, it is shown how aflatoxins can be determined in biological material. The thesis is a summary of five papers.Aflatoxins are carcinogenic mycotoxins produced by Aspergillus moulds. Methods were developed for the determination of aflatoxins in samples of airborne dust and human urine collected at feed factories. READ MORE

7. 5. Determination of biomarkers for lipid peroxidation and oxidative stress : Development of analytical techniques and methods

   Author : Kristina Claeson Bohnstedt; Bo Karlberg; Niels Heegaard; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; capillary electrophoresis; mass spectrometry; electrospray; porous graphitic carbon; oxidative stress; lipid peroxidation; biomarker; malondialdehyde; hydroxynonenal; isoprostane; Analytical chemistry; Analytisk kemi;

   Abstract : Oxidative stress can be defined as a state of disturbance in the pro-oxidant/antioxidant balance in favour of the former, leading to potential damage. Processes associated with oxidative stress involve reactive oxygen species and radicals and can result in elevated levels of oxidatively modified or toxic molecules that can cause cellular malfunction, and even cell death. READ MORE