TY - CONF A1 - Koch, Matthias T1 - Novel reference materials for mycotoxin analysis T2 - Konferenz zum 50. Jahrestag des JRC's IRMM CY - Geel, Belgium DA - 2010-11-23 PY - 2010 AN - OPUS4-21784 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kuner, Maximilian A1 - Kühn, S. A1 - Haase, H. A1 - Meyer, Klas A1 - Koch, Matthias T1 - Cleaving Ergot Alkaloids by Hydrazinolysis - A Promising Approach for a Sum Parameter Screening Method N2 - Ergot alkaloids are mycotoxins formed by fungi of the Claviceps genus, which are some of the most common contaminants of food and feed worldwide. These toxins are a structurally heterogeneous group of compounds, sharing an ergoline backbone. Six structures and their corresponding stereoisomers are typically quantified by either HPLC-FLD or HPLC-MS/MS and the values subsequently summed up to determine the total ergot alkaloid content. For the development of a screening method targeting all ergot alkaloids simultaneously, the alkaloids need to be transferred to one homogeneous structure: a lysergic acid derivative. In this study, two promising cleaving methods—acidic esterification and hydrazinolysis—are compared, using dihydroergocristine as a model compound. While the acidic esterification proved to be unsuitable, due to long reaction times and oxidation sensitivity, hydrazinolysis reached a quantitative yield in 40-60 min. Parallel workup of several samples is possible. An increasing effect on the reaction rate by the addition of ammonium iodide was demonstrated. Application of hydrazinolysis to a major ergot alkaloid mix solution showed that all ergopeptines were cleaved, but ergometrine/-inine was barely affected. Still, hydrazinolysis is a suitable tool for the development of a sum parameter screening method for ergot alkaloids in food and feed. KW - Ergot alkaloids KW - Sum parameter method KW - Hydrazinolysis KW - Esterification PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527508 DO - https://doi.org/10.3390/toxins13050342 VL - 13 IS - 5 SP - 342 PB - MDPI CY - Basel, Switzerland AN - OPUS4-52750 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koch, Matthias T1 - Zearalenone in maize germ oil - a new CRM for food safety T2 - 14th International Symposium on Biological and Environmental Reference Materials (BERM 14) CY - National Harbor, Maryland (USA) DA - 2015-10-11 PY - 2015 AN - OPUS4-34672 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Temgoua Tonleu, Ranil C. A1 - Koch, Matthias T1 - Simulation of the Environmental Degradation of TBBPA by EC-LC-MS N2 - Oxidative degradation processes of tetrabromobisphenol A (TBBPA), a brominated flame retardant (BFR) in wood, plastics and electronics, were investigated by electrochemistry (EC) coupled online to electrospray ionization mass spectrometry (ESI/MS). Oxidative phase I and II metabolites production was achieved using an electrochemical flow-through cell equipped with a boron doped diamond electrode. Structural elucidation and prediction of oxidative metabolism pathways of TBBPA according to type II ipso-substitution were based on retention time, m/z ratio in negative mode and fragmentation pattern. Using the data obtained through high resolution MS analysis and the identification of single electron transfer (SET) as the initial step of a two-electron oxidation provided the necessary information to propose a mechanism for the electrochemical oxidation of TBBPA. Oxidation reactions involving aromatic hydroxylation and β-scission were the main degradation observed when studying the electrochemical behavior of TBBPA. Computational chemistry experiments using density functional theory (DFT) allowed to identify mono-hydroxylated reaction intermediate and dismissed the mechanism involving two concurrent hydroxylation. TBBPA oxidation products were compared to known metabolites of its biological and environmental degradation confirming the ability of electrochemistry to simulate β-scission reactions. T2 - Mass Spectrometry Forum 2024 CY - Vienna, Austria DA - 21.02.2024 KW - Emerging pollutants KW - Chemical characterization KW - Electrochemistry KW - Chemical and material safety KW - Mass spectrometry KW - Environment-material interactions PY - 2024 AN - OPUS4-59571 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Siegel, David A1 - Merkel, Stefan A1 - Bremser, Wolfram A1 - Koch, Matthias A1 - Nehls, Irene T1 - Degradation kinetics of the Alternaria mycotoxin tenuazonic acid in aqueous solutions N2 - The degradation kinetics of the Alternaria mycotoxin tenuazonic acid (l-TA) in aqueous buffer were studied over a period of 4 months at different pH levels (3.5 and 7.0) and temperatures (4, 25 and 40°C). l-TA and its degradation products were quantified by newly developed high-performance liquid chromatography methods with UV or electrospray multistage mass spectrometry detection. At pH 3.5, significant degradation occurred at 25 and 40°C, the respective l-TA half-lives being 73.8±0.4 and 14.0±0.1 days. Two degradation processes, epimerization and hydrolysis, were evaluated kinetically. The hydrolytically formed iso-deacetyl TA (iso-DTA, epimeric mixture) was found to be the stable end product of l-TA degradation under the conditions of this study. This indicates that iso-DTA as well as the l-TA epimer u-TA are formed in aqueous beverage matrices. KW - Tenuazonic acid KW - Alternaria KW - Epimerization KW - Degradation KW - Kinetics PY - 2010 DO - https://doi.org/10.1007/s00216-009-3288-5 SN - 1618-2642 SN - 1618-2650 VL - 397 IS - 2 SP - 453 EP - 462 PB - Springer CY - Berlin AN - OPUS4-21373 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Monavari, Mehran A1 - Prellwitz, Matthias A1 - Koch, Claudia A1 - van de Kreeke, Johannes A1 - Melzer, Michael A1 - Richter, Silke T1 - The Digital Reference Material Document: From Paper Certificates to Interoperable Data Objects in Digital Quality Infrastructure N2 - Reference materials (RMs) are essential for traceable and reliable measurements in science and industry, yet their certificate/document remain largely paper-based. The Digital Reference Material Document (DRMD) project at BAM introduces a transformative approach by converting traditional RM certificates/documents into machine-interpretable, XML-based digital assets. Building on the Digital Calibration Certificate framework, DRMDs encode ISO 33401 requirements and integrate semantic standards like D-SI and material identifiers. These digital documents support automated data exchange, integration into laboratory systems, and interoperability e.g. via asset administration shells and data spaces. The paper presents the DRMD schema concept, and outlines the path toward international harmonization and large-scale deployment, positioning DRMDs as a cornerstone of a digital quality infrastructure. T2 - IMEKO TC-6 International Conference on Metrology and Digital Transformation - M4DConf 2025 DA - 03.09.2025 KW - Digital Reference Material Document KW - Quality Infrastructure KW - Reference Material Certificate KW - DRMD PY - 2025 UR - https://www.m4dconf.org/ UR - https://www.sciencedirect.com/journal/measurement-digitalization SP - 1 EP - 6 AN - OPUS4-64269 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weiz, S. A1 - Marten, S. A1 - Heinze, J. A1 - Drzymala, Sarah A1 - Koch, Matthias T1 - Unpolarer Analyt, unpolare Matrix: das Mykotoxin Zearalenon in Öl N2 - Mit einer automatisierten Online-Festphasenextraktion ist das Schimmelpilzgift Zearalenon in Speiseöl mit HPLC direkt bestimmbar. Die Probenvorbereitung ist hochselektiv und eignet sich für die Routinekontrolle des EU-Grenzwerts. KW - Mykotoxine KW - HPLC KW - Online-SPE KW - Hydrazine PY - 2013 SN - 1439-9598 SN - 1521-3854 VL - 61 IS - Dezember SP - 1241 EP - 1243 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-29811 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koch, Matthias T1 - Certification of new reference materials - Fusarium mycotoxins in food T2 - 39. Deutscher Lebensmittelchemikertag CY - Stuttgart, Germany DA - 2010-09-20 PY - 2010 AN - OPUS4-20974 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koch, Matthias T1 - Fusarium mycotoxins in food - Development of new reference materials T2 - ANALYTICA CY - Munich, Germany DA - 2010-03-23 PY - 2010 AN - OPUS4-20943 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Pielhau, Ramona A1 - Koch, Matthias T1 - Evaluation of an extraction method and spin column cleanup procedure for Fusarium mycotoxins and their masked derivatives from grain matrix N2 - Fusarium mycotoxins in foodstuffs at levels in violation of allowed legal limits belong to the most frequently occurring type of food contamination. Out of the large variety of known mycotoxins, deoxynivalenol (DON), zearalenone (ZEN), and the T-toxins are the most prevalent and are responsible for extensive and recurring economic damage. For ensuring consumer safety, it is required to continually identify faster, simpler and more reliable analytical methodologies. In the present work, miniaturized centrifugation (spin) columns for the extraction of mycotoxins from grain samples were investigated, with a focus on matrix removal, applicability of different extraction solvents, and recovery of mycotoxin. The method was further extended to the extraction of naturally occurring DON and ZEN conjugates (masked mycotoxins). The spin column method was observed to routinely provide a total matrix reduction of >90% from typical wheat samples in a single centrifugation step. The use of H2O/ACN (20/80; v/v) as an extraction solvent provided non-masked DON, ZEN and T-toxin recoveries of greater than 80%. For the masked DON and ZEN conjugates (DON-3-glucoside and ZEN-14-sulfate), recoveries were lower. Overall, the evaluated miniaturized spin column procedure enabled rapid loss-free extraction of unconjugated mycotoxins from conventional grain matrix and a significantly reduced matrix load in the extracts. KW - Fusarium mycotoxins KW - Spin-columns KW - Cleanup effectiveness KW - Masked mycotoxins KW - Recovery rate PY - 2014 DO - https://doi.org/10.1016/j.foodcont.2013.12.003 SN - 0956-7135 VL - 40 SP - 151 EP - 156 PB - Elsevier CY - Amsterdam AN - OPUS4-31609 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koch, Matthias T1 - On a method to completely recover mineral oil dispersed in water T2 - "Tag der Chemie", FU Berlin CY - Berlin, Germany DA - 2001-11-07 PY - 2001 AN - OPUS4-5830 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -