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  • 1. Avagyan, Rozanna
    et al.
    Nyström, Robin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Westerholm, Roger
    Determination of hydroxylated polycyclic aromatic hydrocarbons by HPLC-photoionization tandem mass spectrometry in wood smoke particles and soil samples2015In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 407, no 16, p. 4523-4534Article in journal (Refereed)
    Abstract [en]

    A simple and fast method for analysis of hydroxylated polycyclic aromatic hydrocarbons using pressurized liquid extraction and high performance liquid chromatography utilizing photoionization tandem mass spectrometry was developed. Simultaneous separation and determination of nine hydroxylated polycyclic aromatic hydrocarbons and two hydroxy biphenyls could be performed in negative mode with a run time of 12 min, including equilibration in 5 min. The calibration curves were in two concentration ranges; 1-50 ng/mL and 0.01-50 mu g/mL, with coefficients of correlation R (2) > 0.997. The limits of detection and method quantification limits were in the range of 9-56 pg and 5-38 ng/g, respectively. A two-level full factorial experimental design was used for screening of conditions with the highest impact on the extraction. The extraction procedure was automated and suitable for a large number of samples. The extraction recoveries ranged from 70 to 102 % and the matrix effects were between 92 and 104 %. The overall method was demonstrated on wood smoke particles and soil samples with good analytical performance, and five OH-PAHs were determined in the concentration range of 0.19-210 mu g/g. As far as we know, hydroxylated polycyclic aromatic hydrocarbons were determined in wood smoke and soil samples using photoionization mass spectrometry for the first time in this present study. Accordingly, this study shows that high performance liquid chromatography photoionization tandem mass spectrometry can be a good option for the determination of hydroxylated polycyclic aromatic hydrocarbons in complex environmental samples.

  • 2. Bergknut, Magnus
    et al.
    Persson, Per
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Skyllberg, Ulf
    Molecular characterization of brominated persistent pollutants using extended X-ray absorption fine structure (EXAFS) spectroscopy2008In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 390, no 3, p. 921-928Article in journal (Refereed)
    Abstract [en]

    X-ray absorption fine structure (EXAFS) spectroscopy spectra were collected for three brominated persistent pollutants: 6-bromo-2,4,5-trichlorophenol (BrTriClP), pentabromophenol (PentaBrP) and 3,3',5,5'-tetrabromobisphenol A (TBBA). The substances were selected to be symmetrical (BrTriClP and TBBA) or asymmetrical (PentaBrP) with respect to the atomic Br positions and to differ in the number of bromine and other halide atoms, as well as their relative positions. The asymmetrical PentaBrP was modelled with special detail as not all bromine atoms have identical coordination environments. The studied substances displayed unique EXAFS spectra, which could be used to determine the molecular structure in fair detail. We conclude that EXAFS spectroscopy is a suitable technique for molecular characterization of the comparatively complex molecules within the class of compounds of brominated organic persistent pollutants. A detailed understanding of the EXAFS spectra of the pure compounds opens up possibilities to study the interactions with soil and sediment matrices by means of EXAFS spectroscopy. Figure Brominated organic persistent pollutants are characterized by EXAFS spectroscopy.

  • 3.
    Claeson, Anna-Sara
    et al.
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine.
    Östin, Anders
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine.
    Sunesson, Anna-Lena
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine.
    Development of a LC-MS/MS method for the analysis of volatile primary and secondary amines as NIT (naphthylisothiocyanate) derivatives2004In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 378, no 4, p. 932-939Article in journal (Refereed)
  • 4.
    Gallampois, Christine M. J.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Department of Effect-Directed Analysis, UFZ—Helmholtz Centre for Environmental Research, Leipzig, Germany.
    Schymanski, Emma L.
    Bataineh, Mahmoud
    Buchinger, Sebastian
    Krauss, Martin
    Reifferscheid, Georg
    Brack, Werner
    Integrated biological-chemical approach for the isolation and selection of polyaromatic mutagens in surface waters2013In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 405, no 28, p. 9101-9112Article in journal (Refereed)
    Abstract [en]

    Many environmental mutagens, including polyaromatic compounds are present in surface waters, often in complex mixtures and at low concentrations. The present study provides and applies a novel, integrated approach to isolate polyaromatic mutagens in river water using a sample from the River Elbe. The sample was taken downstream of industrial discharges using blue rayon (BR) as a passive sampler that selectively adsorbs polyaromatic compounds and was subjected to effect-directed fractionation in order to characterise the compounds causing the detected effect(s). The procedure relies on three complementary fractionation steps, the Ames fluctuation assay with strains TA98, YG1024 and YG1041 with and without S9 activation and analytical screening. Several mutagenic fractions were isolated by combining mutagenicity testing with fractionation. The enhanced mutagenicity in the nitroreductase and/or O-acetyltransferase overexpressing strains YG1024 and YG1041 strains suggested amino- and/or nitro-compounds causing mutagenicity in several fractions. Analytical screening of mutagenic fractions with LC-HRMS/MS provided a list of molecular formulas typically containing one to ten nitrogen and at least two oxygen atoms supporting the presence of amino and nitro-compounds in the mutagenic fractions.

  • 5.
    Gouveia-Figueira, Sandra
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Karimpour, Masoumeh
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Bosson, Jenny A.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Blomberg, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Unosson, Jon
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Pourazar, Jamshid
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Sandström, Thomas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Behndig, Annelie F.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Nording, Malin L.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Mass spectrometry profiling of oxylipins, endocannabinoids, and N-acylethanolamines in human lung lavage fluids reveals responsiveness of prostaglandin E2 and associated lipid metabolites to biodiesel exhaust exposure2017In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 409, no 11, p. 2967-2980Article in journal (Refereed)
    Abstract [en]

    The adverse effects of petrodiesel exhaust exposure on the cardiovascular and respiratory systems are well recognized. While biofuels such as rapeseed methyl ester (RME) biodiesel may have ecological advantages, the exhaust generated may cause adverse health effects. In the current study, we investigated the responses of bioactive lipid mediators in human airways after biodiesel exhaust exposure using lipidomic profiling methods. Lipid mediator levels in lung lavage were assessed following 1-h biodiesel exhaust (average particulate matter concentration, 159 mu g/m(3)) or filtered air exposure in 15 healthy individuals in a double-blinded, randomized, controlled, crossover study design. Bronchoscopy was performed 6 h post exposure and lung lavage fluids, i.e., bronchial wash (BW) and bronchoalveolar lavage (BAL), were sequentially collected. Mass spectrometry methods were used to detect a wide array of oxylipins (including eicosanoids), endocannabinoids, Nacylethanolamines, and related lipid metabolites in the collected BWand BAL samples. Six lipids in the human lung lavage samples were altered following biodiesel exhaust exposure, three from BAL samples and three from BW samples. Of these, elevated levels of PGE2, 12,13-DiHOME, and 13-HODE, all of which were found in BAL samples, reached Bonferroni-corrected significance. This is the first study in humans reporting responses of bioactive lipids following biodiesel exhaust exposure and the most pronounced responses were seen in the more peripheral and alveolar lung compartments, reflected by BAL collection. Since the responsiveness and diagnostic value of a subset of the studied lipid metabolites were established in lavage fluids, we conclude that our mass spectrometry profiling method is useful to assess effects of human exposure to vehicle exhaust.

  • 6.
    Haglund, Peter
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Korytár, Peter
    Danielsson, Conny
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Diaz, Jordí
    Wiberg, Karin
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Leonards, Pim
    Brinkman, Udo
    de Boer, Jacob
    GCxGC-ECD a promising method for the determination of dioxins and dioxin-like PCBs in food and feed2008In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 390, no 7, p. 1815-1827Article in journal (Refereed)
    Abstract [en]

    There is a need for cost-efficient alternatives to gas chromatography (GC)–high-resolution mass spectrometry (HRMS) for the analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (PCBs) in food and feed. Comprehensive two-dimensional GC–micro electron capture detection (GC×GC-μECD) was tested and all relevant (according to the World Health Organisation, WHO) PCDD/Fs and PCBs could be separated when using a DB-XLB/LC-50 column combination. Validation tests by two laboratories showed that detectability, repeatability, reproducibility and accuracy of GC×GC-μECD are all statistically consistent with GC-HRMS results. A limit of detection of 0.5 pg WHO PCDD/F tetrachlorodibenzo-p-dioxin equivalency concentration per gram of fish oil was established. The reproducibility was less than 10%, which is below the recommended EU value for reference methods (less than 15%). Injections of vegetable oil extracts spiked with PCBs, polychlorinated naphthalenes and diphenyl ethers at concentrations of 200 ng/g showed no significant impact on the dioxin results, confirming in that way the robustness of the method. The use of GC×GC-μECD as a routine method for food and feed analysis is therefore recommended. However, the data evaluation of low dioxin concentrations is still laborious owing to the need for manual integration. This makes the overall analysis costs higher than those of GC-HRMS. Further developments of software are needed (and expected) to reduce the data evaluation time. Combination of the current method with pressurised liquid extraction with in-cell cleanup will result in further reduction of analysis costs.

  • 7.
    Kolmert, Johan
    et al.
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå Plant Science Center, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå ; Global Safety Assessment, AstraZeneca R&D, Södertälje ; Department of Analytical Chemistry, Stockholm University.
    Forngren, B.
    Lindberg, J.
    Öhd, J.
    Åberg, K. M.
    Nilsson, G.
    Moritz, T.
    Nordström, Anders
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    A quantitative LC/MS method targeting urinary 1-methyl-4-imidazoleacetic acid for safety monitoring of the global histamine turnover in clinical studies2014In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 406, no 6, p. 1751-1762Article in journal (Refereed)
    Abstract [en]

    Anaphylaxis is a potentially life-threatening condition triggered mainly by the release of inflammatory mediators, notably histamine. In pharmaceutical research, drug discovery, and clinical evaluation, it may be necessary to accurately assess the potential of a compound, event, or disorder to promote the release of histamine. In contrast to the measurement of plasma histamine, determination of the stable metabolite 1-methyl-4-imidazoleacetic acid (tele-MIAA) in urine provides a noninvasive and more reliable methodology to monitor histamine release. This study presents a repeatable high-performance liquid chromatography coupled to electrospray mass spectrometry (LC-ESI-MS) method where tele-MIAA is baseline separated from its structural isomer 1-methyl-5-imidazoleacetic acid (pi-MIAA) and an unknown in human urine. The ion-pairing chromatography method, in reversed-phase mode, based on 0.5 mM tridecafluoroheptanoic acid demonstrated high repeatability and was applied in a clinical development program that comprised a large number of clinical samples from different cohorts. The inter- and intra-run precision of the method for tele-MIAA were 8.4 and 4.3 %, respectively, at the mean urinary concentration level, while method accuracy was between -16.2 and 8.0 % across the linear concentration range of 22-1,111 ng mL(-1). Overall, method precision was greater than that reported in previously published methods and enabled the identification of gender differences that were independent of age or demography. The median concentration measured in female subjects was 3.0 mu mol mmol(-1) of creatinine, and for male subjects, it was 2.1 mu mol mmol(-1) of creatinine. The results demonstrate that the method provides unprecedented accuracy, precision, and practicality for the measurement of tele-MIAA in large clinical settings.

  • 8.
    Lindholm-Sethson, Britta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Nyström, Josefina
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Malmsten, Martin
    Department of Pharmacy, Uppsala University.
    Ringstad, Lovisa
    Department of Pharmacy, Uppsala University.
    Nelson, Andrew
    Centre for Molecular Nanoscience, School of Chemistry, University of Leeds, Leeds, United Kingdom.
    Geladi, Paul
    Unit of Biomass Technology and Chemistry, SLU, Umeå, Sweden.
    Electrochemical impedance spectroscopy in label-free biosensor applications: multivariate data analysis for an objective interpretation2010In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 398, no 6, p. 2341-9Article in journal (Refereed)
    Abstract [en]

    Electrochemical impedance spectroscopy plays an important role in biosensor science thanks to the possibility of finding specific information from processes with different kinetics at a chosen electrode potential in one experiment. In this paper we briefly discuss label-free impedimetric biosensors described in the literature. A novel method for neutral interpretation of impedance data is presented that includes complex number chemometrics. Three examples are given based on impedance measurements on synthetic biomembranes, in this case a lipid monolayer deposited on a mercury electrode. The interaction of various compounds with the monomolecular lipid layer is illustrated with the following: (1) different concentrations of magainin (Geladi et al. in Proc. Int. Fed. Med. Biomed. Eng. 9:219-220, 2005); (2) different derivatives of gramicidin A (Lindholm-Sethson et al. in Langmuir 24:5029-5032, 2007), and (3) an antimicrobial peptide (Ringstad et al. in Langmuir 24:208-216, 2008).

  • 9. Muusse, Martine
    et al.
    Langford, Katherine
    Tollefsen, Knut Erik
    Cornelissen, Gerard
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Hylland, Ketil
    Thomas, Kevin V
    Characterization of AhR agonist compounds in roadside snow2012In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 403, no 7, p. 2047-2056Article in journal (Refereed)
    Abstract [en]

    Aryl hydrocarbon receptor (AhR) agonistic contaminants were identified in roadside snow samples. Snow was collected in Oslo, Norway, and compared to a background sample collected from a mountain area. The water and particulate fractions were analysed for AhR agonists using a dioxin-responsive, chemically activated luciferase expression (CALUX) cell assay and by gas chromatography coupled to high-resolution time-of-flight mass spectrometry with targeted analysis for polycyclic aromatic hydrocarbons (PAHs) and broad-spectrum non-target analysis. The AhR agonist levels in the dissolved fractions in the roadside samples were between 15 and 387 pg/L CALUX toxic equivalents (TEQ(CALUX)). An elevated AhR activity of 221 pg TEQ(CALUX) per litre was detected in the mountain sample. In the particle-bound fractions, the TEQ(CALUX) was between 1,350 and 7,390 pg/L. One possible explanation for the elevated levels in the dissolved fraction of the mountain sample could be the presence of black carbon in the roadside samples, potentially adsorbing dioxin-like compounds and rendering them unavailable for AhR interaction. No polychlorinated dibenzodioxins and dibenzofurans or polychlorinated biphenyls were detected in the samples; the occurrence of PAHs, however, explained up to 9 % of the AhR agonist activity in the samples, whilst comprehensive two-dimensional gas chromatography coupled to mass spectrometry GCxGC-ToF-Ms identified PAH derivatives such as polycyclic aromatic ketones and alkylated, nitrogen sulphur and oxygen PAHs in the particle fractions. The (large) discrepancy between the total and explained activity highlights the fact that there are other as yet unidentified AhR agonists present in the environment.

  • 10.
    Nguyen Van, Dong
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Muppala, Siva Rama Krishna
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Frech, Wolfgang
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Tesfalidet, Solomon
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Preparation, preservation and application of pure isotope-enriched phenyltin species.2006In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 386, no 5, p. 1505-1513Article in journal (Refereed)
    Abstract [en]

    A method combining liquid/liquid extraction and chromatographic fractionation has been developed for the preparation of pure monophenyltin (MPhT), diphenyltin (DPhT), and triphenyltin (TPhT), synthesized from isotope-enriched Sn metal using phenylation of SnI(4) in diethylether (DEE) followed by quenching with HBr and water. After two successive extractions of the aqueous HBr phase with DEE, >99% of both DPhT and TPhT was recovered in the combined DEE phase and 94% of the MPhT remained in the aqueous phase. The MPhT in the aqueous phase was extracted into dichloromethane. The organic phases were vaporized and the PhTs were redissolved in MeOH/water/acetic acid/sodium acetate (59/30/6/8, v/v/v/w), which was also used as storing solution. Aliquots of the two solutions containing either DPhT and TPhT or MPhT were injected into a silica-based C(18) column for isolating and purifying single species. The yields of pure MPhT, DPhT, and TPhT, each synthesized from isotope-enriched (118)Sn metal, (122)Sn metal, and (124)Sn metal, were better than 99%. After chromatographic separation, the single phenyltin compounds were mixed to prepare a spike for multiple-isotope species-specific isotope dilution (MI-SSID). MI-SSID was successfully used to determine phenyltin compounds in the certified reference material, mussel tissue BCR CRM-477. At -20 degrees C, all of the fractionated phenyltin species were stable in the storage solution for at least 197 days. When these standards were stored at 4 degrees C or 22 degrees C, 4-6% of the DPhT and TPhT degraded within 27 days. The degradation of DPhT and TPhT increased with the ionic strength and acidity of the storage solution.

  • 11.
    Nording, Malin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Nichkova, Mikaela
    Department of Entomology and Cancer Research Center, University of California, USA.
    Spinnel, Erik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Persson, Ylva
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Gee, Shirley J.
    Department of Entomology and Cancer Research Center, University of California, USA.
    Hammock, Bruce D.
    Department of Entomology and Cancer Research Center, University of California, USA.
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Rapid screening of dioxin-contaminated soil by accelerated solvent extraction/purification followed by immunochemical detection2006In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 385, no 2, p. 357-366Article in journal (Refereed)
    Abstract [en]

    Since soils at industrial sites might be heavily contaminated with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), there is a need for large-scale soil pollution surveys and, thus, for cost-efficient, high-throughput dioxin analyses. However, trace analysis of dioxins in complex matrices requires exhaustive extraction, extensive cleanup, and very sensitive detection methods. Traditionally, this has involved the use of Soxhlet extraction and multistep column cleanup, followed by gas chromatography-high-resolution mass spectrometry (GC/HRMS), but bioanalytical techniques may allow much more rapid, cost-effective screening. The study presented here explores the possibility of replacing the conventional method with a novel approach based on simultaneous accelerated solvent extraction (ASE) and purification, followed by an enzyme-linked immunosorbent assay (ELISA). Both the traditional and the novel cleanup and detection approaches were applied to contaminated soil samples, and the results were compared. ELISA and GC/HRMS results for Soxhlet-extracted samples were linearly correlated, although the ELISA method slightly underestimated the dioxin levels. To avoid an unacceptable rate of false-negative results, the use of a safety factor is recommended. It was also noted that the relative abundance of the PCDDs/PCDFs, evaluated by principal component analysis, had an impact on the ELISA performance. To minimize this effect, the results may be corrected for differences between the ELISA cross-reactivities and the corresponding toxic equivalency factor values. Finally, the GC/HRMS and ELISA results obtained following the two sample preparation methods agreed well; and the ELISA and GC/HRMS results for ASE extracts were strongly correlated (correlation coefficient, 0.90). Hence, the ASE procedure combined with ELISA analysis appears to be an efficient approach for high-throughput screening of PCDD-/PCDF-contaminated soil samples.

  • 12.
    Nording, Malin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Sporring, Sune
    Department of Analytical Chemistry, Lund University, Lund, Sweden .
    Wiberg, Karin
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Björklund, Erland
    Department of Analytical Chemistry, Lund University, Lund, Sweden .
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Monitoring dioxins in food and feedstuffs using accelerated solvent extraction with a novel integrated carbon fractionation cell in combination with a CAFLUX bioassay2005In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 381, no 7, p. 1472-1475Article in journal (Refereed)
    Abstract [en]

    The concentrations of dioxins in fish oil and fish meal were determined with accelerated solvent extraction, using a novel integrated carbon fractionation extraction cell followed by a miniturized multilayer silica column and bioanalysis on a recently-developed chemically-activated fluorescent gene expression cell bioassay. The developed method allows for simultaneous gravimetric lipid weight determination, which was shown for both matrices under study (about 100% lipid recovery of each sample). Initial results practically meet the quality criteria on screening methods for control of dioxins in food and feedstuffs laid down in the EU Commission Directives 2002/69/EC (food) and 2002/70/EC (feed). This demonstrates that the developed method can be used as a screening tool for monitoring dioxins in food and feed after some additional improvements and testing on a greater number of matrices.

  • 13. Rostkowski, Pawel
    et al.
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Aalizadeh, Reza
    Alygizakis, Nikiforos
    Thomaidis, Nikolaos
    Beltran Arandes, Joaquin
    Nizzetto, Pernilla Bohlin
    Booij, Petra
    Budzinski, Helene
    Brunswick, Pamela
    Covaci, Adrian
    Gallampois, Christine
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Grosse, Sylvia
    Hindle, Ralph
    Ipolyi, Ildiko
    Jobst, Karl
    Kaserzon, Sarit L.
    Leonards, Pim
    Lestremau, Francois
    Letzel, Thomas
    Magner, Jorgen
    Matsukami, Hidenori
    Moschet, Christoph
    Oswald, Peter
    Plassmann, Merle
    Slobodnik, Jaroslav
    Yang, Chun
    The strength in numbers: comprehensive characterization of house dust using complementary mass spectrometric techniques2019In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 411, no 10, p. 1957-1977Article in journal (Refereed)
    Abstract [en]

    Untargeted analysis of a composite house dust sample has been performed as part of a collaborative effort to evaluate the progress in the field of suspect and nontarget screening and build an extensive database of organic indoor environment contaminants. Twenty-one participants reported results that were curated by the organizers of the collaborative trial. In total, nearly 2350 compounds were identified (18%) or tentatively identified (25% at confidence level 2 and 58% at confidence level 3), making the collaborative trial a success. However, a relatively small share (37%) of all compounds were reported by more than one participant, which shows that there is plenty of room for improvement in the field of suspect and nontarget screening. An even a smaller share (5%) of the total number of compounds were detected using both liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS). Thus, the two MS techniques are highly complementary. Most of the compounds were detected using LC with electrospray ionization (ESI) MS and comprehensive 2D GC (GCxGC) with atmospheric pressure chemical ionization (APCI) and electron ionization (EI), respectively. Collectively, the three techniques accounted for more than 75% of the reported compounds. Glycols, pharmaceuticals, pesticides, and various biogenic compounds dominated among the compounds reported by LC-MS participants, while hydrocarbons, hydrocarbon derivatives, and chlorinated paraffins and chlorinated biphenyls were primarily reported by GC-MS participants. Plastics additives, flavor and fragrances, and personal care products were reported by both LC-MS and GC-MS participants. It was concluded that the use of multiple analytical techniques was required for a comprehensive characterization of house dust contaminants. Further, several recommendations are given for improved suspect and nontarget screening of house dust and other indoor environment samples, including the use of open-source data processing tools. One of the tools allowed provisional identification of almost 500 compounds that had not been reported by participants.

  • 14. Schymanski, Emma L
    et al.
    Singer, Heinz P
    Slobodnik, Jaroslav
    Ipolyi, Ildiko M
    Oswald, Peter
    Krauss, Martin
    Schulze, Tobias
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Letzel, Thomas
    Grosse, Sylvia
    Thomaidis, Nikolaos S
    Bletsou, Anna
    Zwiener, Christian
    Ibáñez, María
    Portolés, Tania
    de Boer, Ronald
    Reid, Malcolm J
    Onghena, Matthias
    Kunkel, Uwe
    Schulz, Wolfgang
    Guillon, Amélie
    Noyon, Naïke
    Leroy, Gaëla
    Bados, Philippe
    Bogialli, Sara
    Stipaničev, Draženka
    Rostkowski, Pawel
    Hollender, Juliane
    Non-target screening with high-resolution mass spectrometry: critical review using a collaborative trial on water analysis2015In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 407, no 21, p. 6237-6255Article, review/survey (Refereed)
    Abstract [en]

    In this article, a dataset from a collaborative non-target screening trial organised by the NORMAN Association is used to review the state-of-the-art and discuss future perspectives of non-target screening using high-resolution mass spectrometry in water analysis. A total of 18 institutes from 12 European countries analysed an extract of the same water sample collected from the River Danube with either one or both of liquid and gas chromatography coupled with mass spectrometry detection. This article focuses mainly on the use of high resolution screening techniques with target, suspect, and non-target workflows to identify substances in environmental samples. Specific examples are given to emphasise major challenges including isobaric and co-eluting substances, dependence on target and suspect lists, formula assignment, the use of retention information, and the confidence of identification. Approaches and methods applicable to unit resolution data are also discussed. Although most substances were identified using high resolution data with target and suspect-screening approaches, some participants proposed tentative non-target identifications. This comprehensive dataset revealed that non-target analytical techniques are already substantially harmonised between the participants, but the data processing remains time-consuming. Although the objective of a "fully-automated identification workflow" remains elusive in the short term, important steps in this direction have been taken, exemplified by the growing popularity of suspect screening approaches. Major recommendations to improve non-target screening include better integration and connection of desired features into software packages, the exchange of target and suspect lists, and the contribution of more spectra from standard substances into (openly accessible) databases.

  • 15.
    Spinnel, Erik
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Danielsson, Conny
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Rapid and cost-effective analysis of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in soil, fly ash and sediment certified reference materials using pressurized liquid extraction with an integrated carbon trap2008In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 390, no 1, p. 411-417Article in journal (Refereed)
    Abstract [en]

    Pressurized liquid extraction with an integrated carbon trap (PLE-C) has recently been developed for fast and efficient analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in food and feed. The method has also been tested, but not verified, for use on more complex soil samples, such as soil, sediment and fly ash. Hence, the primary aim of this study was to verify that PLE-C can produce reliable data for PCDDs/PCDFs in various abiotic matrixes. A second aim was to find a replacement for the previously used AX21 active carbon that is currently not commercially available. The performance of the PLE-C was evaluated using both single congener concentrations and toxic equivalency potentials (TEQ-pot) of three (soil, sediment and fly ash) certified reference materials. The results clearly show that PLE-C can be used for abiotic samples and that a commercially available carbon (Norit SA 4PAH HF) can replace the AX-21 carbon in the carbon trap. The TEQ-pot values obtained for the soil and sediment samples were within the uncertainty limits of the corresponding certified values, as were the determinations of single congener concentrations. PLE-C therefore has great potential for determination of PCDDs/PCDFs in soil and sediment samples. The TEQ-pot result for the fly ash was slightly lower than the certified TEQ-pot value, but it is still within the uncertainty limits of the certified value. Out of the single congener concentrations all but four (out of 17) agreed well with the values. Hence, PLE-C may potentially be used also for fly ash-after slight modifications. The integrated PLE-C and cleanup procedure is less labour-intensive than traditional methods such as Soxhlet extraction followed by a multistep cleanup, and consumes smaller quantities of ultrapure solvents than the commonly used Power-Prep system. In addition, PLE-C is capable of larger sample throughputs than the conventional methods. Thus, PLE-C is a promising alternative to the currently used sample preparation procedures for dioxins in abiotic samples. Figure PLE with integraded carbon trap for rapid PCDD/Fs analysis.

  • 16.
    Surowiec, Izabella
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Karimpour, Masoumeh
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Gouveia-Figueira, Sandra
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Wu, Junfang
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Unosson, Jon
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Bosson, Jenny A.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Blomberg, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Pourazar, Jamshid
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Sandström, Thomas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Behndig, Annelie F.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Trygg, Johan
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Nording, Malin L.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Multi-platform metabolomics assays for human lung lavage fluids in an air pollution exposure study2016In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 408, no 17, p. 4751-4764Article in journal (Refereed)
    Abstract [en]

    Metabolomics protocols are used to comprehensively characterize the metabolite content of biological samples by exploiting cutting-edge analytical platforms, such as gas chromatography (GC) or liquid chromatography (LC) coupled to mass spectrometry (MS) assays, as well as nuclear magnetic resonance (NMR) assays. We have developed novel sample preparation procedures combined with GC-MS, LC-MS, and NMR metabolomics profiling for analyzing bronchial wash (BW) and bronchoalveolar lavage (BAL) fluid from 15 healthy volunteers following exposure to biodiesel exhaust and filtered air. Our aim was to investigate the responsiveness of metabolite profiles in the human lung to air pollution exposure derived from combustion of biofuels, such as rapeseed methyl ester biodiesel, which are increasingly being promoted as alternatives to conventional fossil fuels. Our multi-platform approach enabled us to detect the greatest number of unique metabolites yet reported in BW and BAL fluid (82 in total). All of the metabolomics assays indicated that the metabolite profiles of the BW and BAL fluids differed appreciably, with 46 metabolites showing significantly different levels in the corresponding lung compartments. Furthermore, the GC-MS assay revealed an effect of biodiesel exhaust exposure on the levels of 1-monostearylglycerol, sucrose, inosine, nonanoic acid, and ethanolamine (in BAL) and pentadecanoic acid (in BW), whereas the LC-MS assay indicated a shift in the levels of niacinamide (in BAL). The NMR assay only identified lactic acid (in BW) as being responsive to biodiesel exhaust exposure. Our findings demonstrate that the proposed multi-platform approach is useful for wide metabolomics screening of BW and BAL fluids and can facilitate elucidation of metabolites responsive to biodiesel exhaust exposure.

  • 17.
    Veenaas, Cathrin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Methodology for non-target screening of sewage sludge using comprehensive two-dimensional gas chromatography coupled to high-resolution mass spectrometry2017In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 409, no 20, p. 4867-4883Article in journal (Refereed)
    Abstract [en]

    To investigate the wide range of pollutants occurring in sewage sludge, an analytical method for comprehensive nontarget screening is needed. To the best of our knowledge, no procedures currently exist for the full screening of organic contaminants in sewage sludge, which is the ultimate goal of this project. We developed non-discriminating sample preparation methods for gas chromatography-mass spectrometry (GC-MS) analysis. Pressurized liquid extraction (PLE) was used for extraction, with in-line (silica gel selective PLE, SPLE) or off-line clean-up (gel permeation chromatography, GPC). This combination allowed the analysis of non-polar compounds of all sizes and small semi-polar and non-polar compounds. The results show that the combination of SPLE and PLE with GPC is suitable for analysis of established as well as new contaminants. Both methods were validated for 99 compounds with different properties. For all GC suitable analytes, either one of the methods produced acceptable recoveries (64 to 136%). As a test, the two methods were used for non-target screening of Swedish sewage sludge. A tiered approach was used to tentatively identify the sludge contaminants. In total, 1865 and 1593 compounds were found of which 321 and 192 compounds were tentatively identified for the PLE and SPLE method, respectively. For a comprehensive coverage of contaminants, the two methods should be used together, with the PLE method covering a wider polarity range and the SPLE method a wider size range. In addition, polar substances will require liquid chromatography-mass spectrometry analysis, the method for which will be developed soon.

  • 18.
    Veenaas, Cathrin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Linusson, Anna
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Retention-time prediction in comprehensive two-dimensional gas chromatography to aid identification of unknown contaminants2018In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 410, no 30, p. 7931-7941Article in journal (Refereed)
    Abstract [en]

    Comprehensive two-dimensional (2D) gas chromatography (GC×GC) coupled to mass spectrometry (MS, GC×GC-MS), which enhances selectivity compared to GC-MS analysis, can be used for non-directed analysis (non-target screening) of environmental samples. Additional tools that aid in identifying unknown compounds are needed to handle the large amount of data generated. These tools include retention indices for characterizing relative retention of compounds and prediction of such. In this study, two quantitative structure–retention relationship (QSRR) approaches for prediction of retention times (1tR and 2tR) and indices (linear retention indices (LRIs) and a new polyethylene glycol–based retention index (PEG-2I)) in GC × GC were explored, and their predictive power compared. In the first method, molecular descriptors combined with partial least squares (PLS) analysis were used to predict times and indices. In the second method, the commercial software package ChromGenius (ACD/Labs), based on a “federation of local models,” was employed. Overall, the PLS approach exhibited better accuracy than the ChromGenius approach. Although average errors for the LRI prediction via ChromGenius were slightly lower, PLS was superior in all other cases. The average deviations between the predicted and the experimental value were 5% and 3% for the 1tR and LRI, and 5% and 12% for the 2tR and PEG-2I, respectively. These results are comparable to or better than those reported in previous studies. Finally, the developed model was successfully applied to an independent dataset and led to the discovery of 12 wrongly assigned compounds. The results of the present work represent the first-ever prediction of the PEG-2I.

  • 19. Weiss, Jana M.
    et al.
    Andersson, Patrik L.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Zhang, Jin
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Simon, Eszter
    Leonards, Pim E. G.
    Hamers, Timo
    Lamoree, Marja H.
    Tracing thyroid hormone-disrupting compounds: database compilation and structure-activity evaluation for an effect-directed analysis of sediment2015In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 407, no 19, p. 5625-5634Article in journal (Refereed)
    Abstract [en]

    A variety of anthropogenic compounds has been found to be capable of disrupting the endocrine systems of organisms, in laboratory studies as well as in wildlife. The most widely described endpoint is estrogenicity, but other hormonal disturbances, e.g., thyroid hormone disruption, are gaining more and more attention. Here, we present a review and chemical characterization, using principal component analysis, of organic compounds that have been tested for their capacity to bind competitively to the thyroid hormone transport protein transthyretin (TTR). The database contains 250 individual compounds and technical mixtures, of which 144 compounds are defined as TTR binders. Almost one third of these compounds (n = 52) were even more potent than the natural hormone thyroxine (T-4). The database was used as a tool to assist in the identification of thyroid hormone-disrupting compounds (THDCs) in an effect-directed analysis (EDA) study of a sediment sample. Two compounds could be confirmed to contribute to the detected TTR-binding potency in the sediment sample, i.e., triclosan and nonylphenol technical mixture. They constituted less than 1 % of the TTR-binding potency of the unfractionated extract. The low rate of explained activity may be attributed to the challenges related to identification of unknown contaminants in combination with the limited knowledge about THDCs in general. This study demonstrates the need for databases containing compound-specific toxicological properties. In the framework of EDA, such a database could be used to assist in the identification and confirmation of causative compounds focusing on thyroid hormone disruption.

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