| 1. |
- Thuy, Tran Thi, et al.
(author)
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Parallel sample preparation of proteins, from crude samples to crystals ready for MALDI-MS, in an integrated microfluidic system
- 2010
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In: Journal of chromatography. B. - : Elsevier BV. - 1570-0232 .- 1873-376X. ; 878:28, s. 2803-2810
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Journal article (peer-reviewed)abstract
- A microfluidic structure is presented where selective capture of proteins in complex samples, followed by clean-up, enzymatic processing, and MALDI-MS sample preparation of peptides generated, can be performed. The structure uses an affinity column to capture the protein while all other components in the sample are disposed of. The protein of interest is then eluted from the affinity column and captured on a second column on which the enzymatic processing is performed. Salts and hydrophilic contaminants are then removed before the products from the enzymatic reaction are eluted together with a suitable MALDI matrix and the solvent evaporated in a designated MALDI target structure. All steps can be performed automatically in 54 parallel microstructures on a microfluidic compact disc. The process is demonstrated by the selective capture and tryptic digest of recombinant IgG molecules from samples containing other proteins: an excess of bovine serum albumin or spent cell culture media.
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| 2. |
- Amini, Nahid, 1973-
(author)
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Novel Solid Phase Extraction and Mass Spectrometry Approaches to Multicomponent Analyses in Complex Matrices
- 2010
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Doctoral thesis (other academic/artistic)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. In addition, results can be improved by efficient chromatographic separation of the sample components. The elimination of interfering substances is especially important when utilizing mass spectrometry (MS) as a detection technique since they influence the ionization yields. It is also important to optimize ionization methods in order to minimize detection limits.In the work this thesis is based upon, selective solid phase extraction (SPE) materials, a restricted access material (RAM) and graphitized carbon black (GCB) were employed for clean up and/or pre-concentration of analytes in plasma, urine and agricultural drainage water prior to liquid chromatography/mass spectrometry (LC/MS). Two SPE formats, in which GCB was incorporated in µ-traps and disks, were developed for cleaning up small and large volume samples, respectively. In addition, techniques based on use of sub-2 µm C18 particles at elevated temperatures and a linear ion trap (LIT) mass spectrometer were developed to improve the efficiency of LC separation and sensitivity of detection of 6-formylindolo[3,2-b]carbazole (FICZ) metabolites in human urine.It was also found that GCB can serve not only as a SPE sorbent, but also as a valuable surface for surface-assisted laser desorption ionization (SALDI) of small molecules. The dual functionality of GCB was utilized in a combined screening-identification/quantification procedure for fast elimination of negative samples. This may be particularly useful when processing large numbers of samples. SALDI analyses of small molecules was further investigated and improved by employing two kinds of new surfaces: oxidized GCB nanoparticles and silicon nitride.
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| 3. |
- Amini, Nahid, et al.
(author)
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SALDI-MS Signal Enhancement Using Oxidized Graphitized Carbon Black Nanoparticles
- 2009
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In: Journal of the American Society for Mass Spectrometry. - : American Chemical Society (ACS). - 1044-0305 .- 1879-1123. ; 20:6, s. 1207-1213
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Journal article (peer-reviewed)abstract
- The signal intensity of low-molecular-weight compounds analyzed using surface-assisted laserdesorption/ionization time-of-flight mass spectrometry (SALDI-TOF-MS) was significantlyenhanced when oxidized graphitized carbon black (GCB) particles were used as the desorption/ionization surface. The surface of oxidized GCB contains more carboxylic acid groupsthan non-oxidized GCB. Carboxylic acid groups enhance the efficiency of the ionizationprocess and the desorption of more hydrophobic compounds. A common pharmaceuticalcompound, propranolol, was successfully extracted from Baltic Sea blue mussels and quantifiedusing oxidized GCB as the SALDI surface, whereas deuterated propranolol was used asthe internal standard. The calibration curve showed a wide linear dynamic range of response(0.1–20 g/mL) and good reproducibility (RSD 10%). It was not possible to detectpropranolol in Baltic Sea blue mussels when non-oxidized GCB was used as the SALDI surface.
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| 4. |
- Amini, Nahid, et al.
(author)
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Screening and Quantification of Pesticides in Water Using a Dual-Function Graphitized Carbon Black Disk
- 2010
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In: Analytical Chemistry. - : ACS. - 0003-2700 .- 1520-6882. ; 82:1, s. 290-296
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Journal article (peer-reviewed)abstract
- A simple platform for combining solid phase extraction (SPE) and surface-assisted laser desorption ionization mass spectrometry (SALDI-MS) of extracted analytes, using disks prepared by embedding graphitized carbon black (GCB-4) particles in a network of polytetrafluoroethylene (PTFE), is presented. The system provides a convenient approach for rapid SALDI-MS screening of substances in aqueous samples, which can be followed by robust quantitative and/or structural analyses by liquid chromatography (LC)/MS/MS of positive samples. The extraction discs are easily transferred between gaskets where the sample extraction and desorption of selected samples is performed and the mass spectrometer. The SPE and SALDI properties of the new GCB-4 disc have been characterized for 15 pesticides with varying chemical properties, and the screening strategy has been applied to the analysis of pesticides in agricultural drainage water. Atrazine and atrazine-desethyl-2-hydroxy were detected in the sampled water by SALDI-MS screening and subsequently confirmed and quantified using LC/MS/MS.
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| 5. |
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| 6. |
- Andersson, Lars Gustaf, et al.
(author)
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Historical Dictionary of Scandinavian Cinema
- 2012
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Book (other academic/artistic)abstract
- Scandinavian cinema—consisting of films produced in Norway, Sweden, Denmark, Finland, and Iceland—has been the source of some of the world's most interesting films—The Seventh Seal, Dancer in the Dark, and The Girl with the Dragon Tattoo—and most influential directors—Ingmar Bergman and Lars von Trier. The Historical Dictionary of Scandinavian Cinema covers the history of the Nordic countries through a chronology, introductory essays on each country, and an extensive bibliography. The dictionary section has over 400 cross-referenced entries on major persons and films, pan-Scandinavian entries on film genres, themes, and subjects such as animation, ethnicity, migration and censorship. This book is an excellent access point for students, researchers, and anyone wanting to know more about Scandinavian cinema.
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| 7. |
- Avagyan, Rozanna, et al.
(author)
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Benzothiazole, benzotriazole, and their derivates in clothing textiles - a potential source of environmental pollutants and human exposure
- 2015
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In: Environmental Science and Pollution Research. - : Springer Science and Business Media LLC. - 0944-1344 .- 1614-7499. ; 22:8, s. 5842-5849
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Journal article (peer-reviewed)abstract
- Textiles play an important role in our daily life, and textile production is one of the oldest industries. In the manufacturing chain from natural and/or synthetic fibers to the final clothing products, the use of many different chemicals is ubiquitous. A lot of research has focused on chemicals in textile wastewater, but the knowledge of the actual content of harmful chemicals in clothes sold on the retail market is limited. In this paper, we have focused on eight benzothiazole and benzotriazole derivatives, compounds rated as high production volume chemicals. Twenty-six clothing samples of various textile materials and colors manufactured in 14 different countries were analyzed in textile clothing using liquid chromatography tandem mass spectrometry. Among the investigated textile products, 11 clothes were for babies, toddlers, and children. Eight of the 11 compounds included in the investigation were detected in the textiles. Benzothiazole was present in 23 of 26 investigated garments in concentrations ranging from 0.45 to 51 μg/g textile. The garment with the highest concentration of benzothiazole contained a total amount of 8.3 mg of the chemical. The third highest concentration of benzothiazole (22 μg/g) was detected in a baby body made from “organic cotton” equipped with the “Nordic Ecolabel” (“Svanenmärkt”). It was also found that concentrations of benzothiazoles in general were much higher than those for benzotriazoles. This study implicates that clothing textiles can be a possible route for human exposure to harmful chemicals by skin contact, as well as being a potential source of environmental pollutants via laundering and release to household wastewater.
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| 8. |
- Avagyan, Rozanna, et al.
(author)
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Determination of benzothiazole and benzotriazole derivates in tire and clothing textile samples by high performance liquid chromatography-electrospray ionization tandem mass spectrometry
- 2013
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In: Journal of Chromatography A. - : Elsevier BV. - 0021-9673 .- 1873-3778. ; 1307, s. 119-125
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Journal article (peer-reviewed)abstract
- A high performance liquid chromatography–tandem mass spectrometry method utilizing electrospray ionization in positive and negative mode has been developed for the separation and detection of benzothiazole and benzotriazole derivates. Ultra-sonication assisted solvent extraction of these compounds has also been developed and the overall method demonstrated on a selected clothing textile and an automobile tire sample. Matrix effects and extraction recoveries, as well as linearity and limits of detection have been evaluated. The calibration curves spanned over more than two orders of magnitude with coefficients of correlation R2 > 0.99 and the limits of detection and the limits of quantification were in the range 1.7–58 pg injected and 18–140 pg/g, respectively. The extraction recoveries ranged between 69% and 102% and the matrix effects between 75% and 101%. Benzothiazole and benzotriazole derivates were determined in the textile sample and benzothiazole derivatives determined in the tire sample with good analytical performance.
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| 9. |
- Awad, Raed, et al.
(author)
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Sampling of PFAS in air
- 2023
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Reports (other academic/artistic)abstract
- Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a group of more than 4000 human-made substances that, due to their unique properties as being water-lipid repellent, and having high chemical and thermal stability, are widely used in consumer products and industrial applications. Examples of the wide range of uses for PFAS are in pesticides, food packaging material, nonstick cookware, furniture wax and fire-fighting foam in fabrics. PFASs are also used as production chemicals for fluorinated polymers in electroplating and they even occur in cosmetics.Scientific studies have shown that exposure to PFASs can lead to adverse health effects in humans. Exposure pathways for PFASs include drinking water contaminated with PFASs, food containing PFASs from packaging material, exposure through skin contact with products containing PFASs as well as through polluted air.
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| 10. |
- Axelsson, Ulrik, et al.
(author)
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Strukturerad miljödatahantering inom järn- och stålindustri
- 2002
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Reports (other academic/artistic)abstract
- Efterfrågan på miljöinformation i olika former förväntas öka under de kommande åren. Det gäller såväl internt inom företaget som externt till kunder, ägare, övriga finansiärer, myndigheter m.fl. För att kunna möta de förväntade kraven har företagen inom järn- och stålindustrin identifierat ett behov av att åstadkomma en strukturerad miljödatahantering (lagring, bearbetning och dokumentation), som möjliggör att ett och samma dataunderlag så långt som möjligt kan utnyttjas och relativt enkelt omformas till olika former av kommunikationsprodukter. Projektets mål är därför att ta fram en branschgemensam struktur för miljödatahantering inom järn- och stålindustrin
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