TY - JOUR A1 - Koch, Matthias A1 - Köppen, Robert A1 - Nehls, Irene T1 - Neue Mykotoxin-Referenzmaterialien - Qualitätssicherung in der Lebensmittelanalytik N2 - Die zuverlässige Überwachung geltender Mykotoxin-Grenzwerte ist elementarer Bestandteil von Lebensmittelsicherheit und Verbraucherschutz. Durch die zunehmende Bedeutung der Qualitätssicherung ist auch die Nachfrage an zertifizierten Referenzmaterialien (ZRM) in den letzten Jahren deutlich gestiegen. Dem steht derzeit jedoch nur eine sehr begrenzte Auswahl geeigneter ZRM gegenüber. KW - Zertifiziertes Referenzmaterial KW - ERM KW - Ochratoxin A KW - Deoxynivalenol KW - Nivalenol KW - Zearalenon KW - Kaffee KW - Wein KW - Weizen PY - 2011 SN - 0012-0413 SN - 1869-2214 IS - September SP - 434 EP - 448 PB - Wiss. Verl.-Ges. CY - Stuttgart AN - OPUS4-24616 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Koch, Matthias A1 - Bremser, Wolfram A1 - Köppen, Robert A1 - Krüger, Rita A1 - Rasenko, Tatjana A1 - Siegel, David A1 - Nehls, Irene T1 - Certification of reference materials for ochratoxin A analysis in coffee and wine N2 - Mycotoxins are important non-anthropogenic food and feed contaminants, which can be present on almost every agricultural commodity. Effective consumer protection therefore essentially depends on food surveillance by reliable quantitative analysis enabled by appropriate quality control. Certified (matrix) reference materials (CRMs) are versatile tools to support Quality assurance. However, in the case of ochratoxin A (OTA), a hepato- and nephrotoxic mycotoxin, which is regulated in various foods, there is a lack of suitable CRMs. This lack has now been overcome by the development of two European Reference Materials (ERM®) for the Determination of OTA in roasted coffee (ERM®-BD475) and red wine (ERM®-BD476). This article discusses the material preparation process as well as the results of homogeneity and stability testing. Furthermore, the results of the inhouse certification studies carried out at BAM Federal Institute for Materials Research and Testing are presented and discussed. Interlaboratory comparison studies involving selected expert laboratories with documented Expertise in the field of mycotoxin analysis were conducted to confirm the certified values determined by BAM. The certified ochratoxin A values and their corresponding expanded uncertainties (k = 2) were assigned in full compliance with the requirements of ISO Guide 35 and are as follows: (6.0 ± 0.6) µg kg-1 for roasted coffee, ERM®-BD475, and (0.52 ± 0.11) µg L-1 for red wine, ERM®-BD476. KW - OTA KW - Coffee KW - Wine KW - Food safety and quality KW - European reference materials KW - CRM PY - 2011 DO - https://doi.org/10.1007/s00769-011-0783-0 SN - 0949-1775 SN - 1432-0517 VL - 16 SP - 429 EP - 437 PB - Springer CY - Berlin AN - OPUS4-24235 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Merkel, Stefan A1 - Köppen, Robert A1 - Koch, Matthias A1 - Emmerling, Franziska A1 - Nehls, Irene T1 - Ergotaminine N2 - The title compound {systematic name: (6aR,9S)-N-[(2R,5S,10aS,10bS)-5-benzyl-10b-hydroxy-2-methyl-3,6-dioxooctahydro-8H-oxazolo[3,2-a]pyrrolo[2,1-c]pyrazin-2-yl]-7-methyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide}, C33H35N5O5, was formed by an epimerization reaction of ergotamine. The non-aromatic ring (ring C of the ergoline skeleton) directly fused to the aromatic rings is nearly planar [maximum deviation = 0.317 (4) Å] and shows an envelope conformation, whereas ring D, involved in an intramolecular N–H···N hydrogen bond exhibits a slightly distorted chair conformation. The structure displays chains running approximately parallel to the diagonal of bc plane that are formed through N–H···O hydrogen bonds. PY - 2012 DO - https://doi.org/10.1107/S1600536812003674 SN - 1600-5368 VL - 68 IS - 3 SP - o610-o611, sup1-sup11 PB - Munksgaard CY - Copenhagen AN - OPUS4-25452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Koch, Matthias A1 - Neuhof, Torsten A1 - Nehls, Irene ED - Jörg Peter Matthes, ED - Markus Frasch, ED - Marx, Wolfram ED - Johannes Oeler, T1 - Lebensmittelanalytik - Neue Referenzmaterialien KW - Referenzmaterialien KW - Acrylamid KW - Ochratoxin A KW - Methylquecksilber PY - 2007 VL - 3 IS - 5 SP - 16 EP - 17 PB - Succidia Verl. & Kommunikation CY - Darmstadt AN - OPUS4-16691 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neuhof, Torsten A1 - Koch, Matthias A1 - Rasenko, Tatjana A1 - Nehls, Irene T1 - Occurrence of zearalenone in wheat kernels infected with Fusarium culmorum N2 - The aim of this study was to investigate the distribution of zearalenone in wheat kernels contaminated with this mycotoxin. Kernels from a sample of a wheat harvest affected by Fusarium culmorum were sorted into six groups according to their visual attributes. Milled portions of these groups were analysed by high-performance liquid chromatography with fluorescence and diode array detection. The clean-up was performed with an immunoaffinity column after methanol/water (4:1, v/v) extraction. The zearalenone content of the unsorted kernel fraction was 74 µg/kg. The group of healthy-looking kernels was contaminated with only 6 µg/kg of zearalenone. The groups of kernels that appeared shrunken and chalky white, damage routinely caused by Fusarium, were contaminated with 170 and 117 µg/kg, respectively. A remarkably high level of zearalenone contamination, 2,184 µg/kg, was observed for the group of reddish kernels. An association between the presence of the red pigment aurofusarin and high levels of zearalenone was found. Therefore, this pigment may be used as a marker of high zearalenone content. KW - Zearalenone KW - Aurofusarin KW - Immunoaffinity column KW - HPLC-FLD/DAD PY - 2008 DO - https://doi.org/10.3920/WMJ2008.1055 SN - 1875-0710 SN - 1875-0796 VL - 1 IS - 4 SP - 429 EP - 435 PB - Wageningen Academic Publishers CY - Wageningen AN - OPUS4-18329 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Retter, Utz A1 - Koch, Matthias A1 - Nehls, Irene T1 - Investigation of the optimization of the recovery of mineral oil from water N2 - A method has been derived to completely recover mineral oil dispersed in water. The method involves three steps: the emulsification of the mineral oil by adding amphiphiles, the breaking of the emulsion by adding salts and the extraction of the mineral oil by a non-polar aprotic solvent. Various amphiphiles and types and concentrations of salts were tested. By using amphiphiles with HLB numbers in the range 4.7 to 40 a complete recovery of the mineral oil could be obtained for a combination of salts Na2SO4 + NaH2PO4 with total ionic strength of 6 mol/L. PY - 1999 SN - 0937-0633 VL - 364 SP - 777 EP - 779 PB - Springer CY - Berlin AN - OPUS4-7524 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nehls, Irene T1 - Ressortforschung und Analytische Chemie - Möglichkeiten und Grenzen T2 - Eingeladener Vortrag im GKSS Institut für Chemie in Teltow-Seehof CY - Teltow, Germany DA - 2005-02-18 PY - 2005 AN - OPUS4-7519 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reinsch, Martin A1 - Töpfer, Antje A1 - Lehmann, Andreas A1 - Nehls, Irene T1 - Determination of ochratoxin A in wine by liquid chromatography tandem mass spectrometry after combined anion-exchange/reversed-phase clean-up N2 - Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus ochraceus and Penicillium verrucosum. It has been found and analysed in several foods and feeds. Owing to its toxicity and occurrence in food and feed, the European Community has issued directives and some countries have their own regulations for OTA contents in food, feed and beverages. This work describes a method for the determination of OTA in mulled and red wine. It is based on combined anion exchange/reversed-phase clean-up and was analysed by liquid chromatography coupled with tandem mass spectrometry (multiple reaction monitoring). The method was validated with natural contaminated and spiked wine samples with OTA contents from 1.34 to 3.48 g kg–1. Owing to its accuracy, good reproducibility and repeatability, this easy method is a good alternative to liquid chromatography–fluorescence detection methods. KW - Ochratoxin A KW - Wine KW - Tandem mass spectrometry KW - Solid-phase extraction KW - Anion exchange KW - Liquid chromatography PY - 2005 DO - https://doi.org/10.1007/s00216-005-3097-4 SN - 1618-2642 SN - 1618-2650 VL - 381 IS - 8 SP - 1592 EP - 1595 PB - Springer CY - Berlin AN - OPUS4-10306 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Koch, Matthias A1 - Krüger, Rita A1 - Nehls, Irene T1 - Referenzmaterialien für Ochratoxin A in Kaffee und Wein KW - Ochratoxin A KW - Referenzmaterial KW - ERM KW - Kaffee KW - Wein PY - 2007 SN - 0937-1478 SN - 1521-3811 VL - 61 IS - 4 SP - 102 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-15723 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nehls, Irene A1 - Koch, Matthias T1 - Zertifizierte Referenzmaterialien für die Mineralölanalytik - Bedeutung für die Kalibrierung KW - Referenzmaterialien PY - 2008 SN - 0016-3538 VL - 8 SP - 718 EP - 719 PB - GIT-Verlag CY - Darmstadt AN - OPUS4-17815 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Rita A1 - Koch, Matthias A1 - Nehls, Irene T1 - Ringversuch für Acrylamid, Theobromin und Coffein in Kakao KW - Ringversuch KW - Acrylamid KW - Theobromin KW - Coffein KW - Kakao PY - 2008 SN - 0937-1478 SN - 1521-3811 VL - 62 IS - 4 SP - 110 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-17848 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neuhof, Torsten A1 - Koch, Matthias A1 - Rasenko, Tatjana A1 - Nehls, Irene T1 - Distribution of Trichothecenes, Zearalenone, and Ergosterol in a Fractionated Wheat Harvest Lot N2 - To investigate possible co-occurrences of type B trichothecenes and zearalenone within a Fusarium culmorum-infected wheat harvest lot, kernels were fractionated into six groups by visual criteria. The Fusarium-damaged kernels were subdivided into white, shrunken, and red kernel groups, and the remaining kernels were sorted into healthy, black spotted, and nonspecific groups. The distribution patterns of nivalenol, deoxynivalenol, zearalenone, and ergosterol were determined for possible correlations. Significant correlations between the distribution patterns were found for the mycotoxins and ergosterol for the grouped kernels (r = 0.997-0.999, p < 0.0001). Additionally, remarkably outstanding levels of nivalenol (24-fold more than the mean at 1.16 mg/kg), deoxynivalenol (27-fold more than the mean at 0.16 mg/kg), zearalenone (25-fold more than the mean at 77 µg/kg), and ergosterol (17-fold more than the mean at 13.4 mg/kg) were found in the red kernel group. Further, detailed mycotoxin and ergosterol analyses were carried out on various segments (kernel surface, conidia, bran, and flour) of the red kernels. However, the mycotoxin and ergosterol distribution profiles revealed nonsignificant correlations for these kernel segments, with the exception of deoxynivalenol and nivalenol, which were moderately correlated (r = 0.948, p = 0.035). KW - Mycotoxins KW - Fusarium-damaged kernels KW - Ergosterol KW - Wheat KW - Correlation KW - HPLC-FLD/DAD PY - 2008 DO - https://doi.org/10.1021/jf800971q SN - 0021-8561 SN - 1520-5118 VL - 56 IS - 16 SP - 7566 EP - 7571 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-18196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neuhof, Torsten A1 - Köppen, Robert A1 - Koch, Matthias A1 - Nehls, Irene T1 - Letter: High-performance liquid chromatography/electrospray mass spectrometry analysis of the mycotoxin aurofusarin N2 - High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) can be used for simultaneous quantification of various mycotoxins in contaminated food samples. Therefore, multi-mycotoxin methods have been developed in the last couple of years. To enlarge these methods for further analytes, we have developed a LC-MS/MS method for the quantification of the mycotoxin aurofusarin. Additionally, further LC-MSn experiments were performed to demonstrate the fragmentation pattern of aurofusarin. Applicable multiple reaction monitoring (MRM) transitions of aurofusarin were found and optimized by parameter variation of the tandem mass spectrometer. The applicability of the developed method was tested by analysis of naturally contaminated wheat. KW - LC-MS/MS KW - Multi-mycotoxin method KW - Aurofusarin PY - 2008 DO - https://doi.org/10.1255/ejms.935 SN - 1469-0667 SN - 1356-1049 SN - 1365-0718 VL - 14 IS - 5 SP - 329 EP - 333 PB - IM Publications CY - Chichester AN - OPUS4-18199 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nehls, Irene T1 - Herstellung und Zertifizierung von BAM-Referenzmaterialien und ihr Einsatz als Instrument der Qualitätssicherung in chemischen Laboratorien T2 - Einladung zum GDCh-Kolloquium an der Friedrich-Schiller-Universität CY - Jena, Germany DA - 2003-06-11 PY - 2003 AN - OPUS4-5863 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dorgerloh, Ute A1 - Erhardt, Ulla A1 - Schmieder, Rosmarie A1 - Walter, W. A1 - Win, Tin A1 - Hilbert, S. A1 - Mechler, M. A1 - Nehls, Irene T1 - Ringversuch zur Bestimmung von leichtflüchtigen halogenierten Kohlenwasserstoffen (LHKW), Vinylchlorid (VC) und Fluorchlorkohlenwasserstoffen (FCKW) in Grundwasser KW - Analytik KW - Grundwasser KW - Leichtflüchtige halogenierte Kohlenwasserstoffe (LHKW) KW - Vinylchlorid (VC) KW - Fluorchlorkohlenwasserstoffe (FCKW) KW - Ringversuch KW - Analytics KW - Groundwater KW - Highly volatile halogenated hydrocarbons (VHHC) KW - Vinyl chloride (VC) KW - Chlorofluorocarbons (CFC) KW - Interlaboratory comparison PY - 2004 SN - 0083-6915 VL - 102 IS - 2 SP - 12 EP - 16 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-4126 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nehls, Irene T1 - Referenzmaterialien - Instrumente der Qualitätssicherung T2 - Kolloquium im Fachbereich Chemie der Humboldt-Universität Berlin CY - Berlin, Germany DA - 2005-02-24 PY - 2005 AN - OPUS4-11738 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Koch, Matthias A1 - Liebich, Almuth A1 - Win, Tin A1 - Nehls, Irene A1 - Kvernheim, A.L. A1 - Ringstad, O. A1 - Oreld, F. T1 - Feasibility studies for the preparation and certification of reference materials - Part II: Mineral oil contaminated waste materials N2 - The 2-year international joint project HYCREF (Contract-No. G6RD-CT-2002-00854), funded by the European Commission in the 5th Framework programme, aimed to develop methods to prepare homogenous and stable water-, soil- and waste reference materials contaminated with mineral oil hydrocarbons and to test certify the mineral oil content by gas chromatographic methods. As mineral oil products are important sources for environmental contaminations, appropriate reference materials certified by using the new gas chromatographic methods (soil: ISO/FDIS 16703, waste: prEN 14039 and KW/04, water: ISO 9377-2) are highly needed. Additional to the HYCREF-results presented in part I–mineral contaminated soils–this second paper gives an overview of the feasibility study for the preparation and test certification of three waste reference materials (offshore marine sediment, building material and industrial waste). The following specifications, which had been defined in the project work plan, were reached successfully: uncertainty of the mineral oil content resulting from the certification exercise ≤ 5% and a between-bottle inhomogeneity of ≤ 3%. All three materials have been evaluated for long- and short term stability. They contain different levels and types of mineral oil and cover the full application range of ISO/FDIS 16703 and prEN 14039 (100–10,000 mg/kg). The expanded uncertainties U cert of the three materials are about 6%. In this way, they are comparable to ERM®-CC015a (U cert=7.1%, mineral oil in a river sediment) and are suited to close the present gap of commercially available CRM for mineral oil determination in waste. KW - Mineral oil hydrocarbons KW - Feasibility study KW - Certified reference materials (CRM) KW - Waste materials KW - Gas chromatography PY - 2006 SN - 0949-1775 SN - 1432-0517 VL - 11 IS - 3 SP - 122 EP - 129 PB - Springer CY - Berlin AN - OPUS4-12392 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neuhof, Torsten A1 - Ganzauer, Natalie A1 - Koch, Matthias A1 - Nehls, Irene T1 - A comparison of chromatographic methods for the determination of deoxynivalenol in wheat N2 - Liquid chromatography coupled with tandem mass spectrometric detection has gained more importance for mycotoxin determination in recent years. In addition to instrumental improvements, the development of LC-MS-MS has also been a consequence of the availability of stable isotope internal standards, e.g., 13C-labelled mycotoxins. Thus, the LC-ESI-MS-MS method using a 13C15-deoxynivalenol internal standard as a state-of-the-art technique was selected as a reference procedure for an in-house method comparison study of the determination of deoxynivalenol (DON) in wheat materials. Alternative methods include LC-diode array detection, which is a frequently used routine procedure for DON-analysis, and gas chromatography after trimethylsilylation. For GC application, an electron capture detector and a negative chemical ionisation mass spectrometry detector were used, which have both been well described in the literature. The method comparison was conducted using t test statistics. Additionally, this study also calculates important method performance characteristics, including accuracy, linearity, limit of detection, limit of quantification, recovery, and variation coefficient. Furthermore, this is the first report of a GC-MS method for the determination of DON using a fully carbon-labelled 13C15-DON as an IS. The GC-MS using 13C15-DON as an IS has produced comparable results to the 13C-IS-LC-MS-MS reference method with a similar sensitivity. ECD detection was slightly less sensitive, but is also suited for DON analysis in wheat. Due to the high LOQ, the LC-DAD method seems highly applicable to the measurement of highly contaminated samples. KW - Column liquid chromatography-mass spectrometry KW - Gas chromatography KW - Mycotoxins KW - Trichothecenes PY - 2009 DO - https://doi.org/10.1365/s10337-009-1084-1 SN - 0009-5893 SN - 1612-1112 VL - 69 IS - 11-12 SP - 1457 EP - 1462 PB - Vieweg CY - Wiesbaden AN - OPUS4-19618 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Siegel, David A1 - Merkel, Stefan A1 - Koch, Matthias A1 - Emmerling, Franziska A1 - Nehls, Irene T1 - 3-{1-[(2,4-Dinitrophenyl)hydrazino]ethylidene}-5-(1-methylpropyl)pyrrolidine-2,4-dione KW - Tenuazonic acid 2,4-dinitrophenylhydrazone KW - X-ray single crystal diffraction KW - Crystal structure PY - 2009 DO - https://doi.org/10.1107/S1600536809012458 SN - 1600-5368 VL - 65 IS - 5 SP - o988 EP - o989 PB - Munksgaard CY - Copenhagen AN - OPUS4-19736 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gärtner, Sonja A1 - Balski, Matthias A1 - Koch, Matthias A1 - Nehls, Irene T1 - Analysis and migration of phthalates in infant food packed in recycled paperboard N2 - The contamination of infant food with substances from its packaging due to migration processes is still a problem. Most recently, great attention was paid to the migration of epoxidized soybean oil (ESBO) and phthalates from twist-off closures into baby food packed in glass jars. Besides, packaging made of recycled fiber materials such as paper and paperboard were found to be the source of contaminants in dry and powdery foodstuffs such as sugar, rice, and maize flour. In this study 20 infant food samples packed in recycled paperboard containers were tested for phthalates and diisopropyl naphthalenes (DIPN), known incorporated substances in recycled paper. Furthermore, the barrier function of different secondary packaging materials (paper and aluminum-coated foil) was investigated. The highest contents of phthalates (mainly diisobutyl phthalate, DiBP) and DIPN in infant food samples were found for those foods packed in inner bags made of paper. Migration experiments were performed under authentic conditions to evaluate possible transfer mechanism (gas phase, direct contact) of phthalate esters into foodstuff. It is shown that paper does not provide an appropriate barrier against migration of semipolar compounds such as phthalates. The air space itself otherwise effectively prevents migration of the less volatile phthalates under the applied conditions. KW - Phthalates KW - Accelerated solvent extraction (ASE) KW - Infant food KW - Recycled paper KW - Migration KW - GC-MS PY - 2009 DO - https://doi.org/10.1021/jf902683m SN - 0021-8561 SN - 1520-5118 VL - 57 IS - 22 SP - 10675 EP - 10681 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-20472 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -