TY - JOUR A1 - Gärtner, Stefanie A1 - Carvalho, J.J. A1 - Emmerling, Franziska A1 - Garbe, L.-A. A1 - Schneider, Rudolf T1 - Polyclonal murine and rabbit antibodies for the bile acid isolithocholic acid N2 - Bile acids are relevant markers for clinical research. This study reports the production of antibodies for isolithocholic acid, the isomer of the extensively studied lithocholic acid. The IgG titer and affinity maturation were monitored during the immunizations of three mice and two rabbits. In both animal models, polyclonal antibodies with a high selectivity and affinity were produced. The development of a direct competitive ELISA with a test midpoint of 0.69 ± 0.05 µg/L and a measurement range from 0.09–15 µg/L is reported. Additionally, the crystal structure of isolithocholic acid is described for the first time. KW - ELISA KW - Crystal structure KW - Competitive assay KW - Immunization monitoring KW - 3ß-hydroxy-5ß-cholanic acid PY - 2015 U6 - https://doi.org/10.1080/15321819.2014.924419 SN - 1532-1819 SN - 1532-4230 VL - 36 IS - 3 SP - 233 EP - 252 PB - Taylor & Francis CY - Philadelphia, Pa. AN - OPUS4-31836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drzymala, Sarah A1 - Weiz, S. A1 - Heinze, J. A1 - Marten, S. A1 - Prinz, Carsten A1 - Zimathies, Annett A1 - Garbe, L.-A. A1 - Koch, Matthias T1 - Automated solid-phase extraction coupled online with HPLC-FLD for the quantification of zearalenone in edible oil N2 - Established maximum levels for the mycotoxin zearalenone (ZEN) in edible oil require monitoring by reliable analytical methods. Therefore, an automated SPE-HPLC online system based on dynamic covalent hydrazine chemistry has been developed. The SPE step comprises a reversible hydrazone formation by ZEN and a hydrazine moiety covalently attached to a solid phase. Seven hydrazine materials with different properties regarding the resin backbone, pore size, particle size, specific surface area, and loading have been evaluated. As a result, a hydrazine-functionalized silica gel was chosen. The final automated online method was validated and applied to the analysis of three maize germ oil samples including a provisionally certified reference material. Important performance criteria for the recovery (70–120 %) and precision (RSDr <25 %) as set by the Commission Regulation EC 401/2006 were fulfilled: The mean recovery was 78 % and RSDr did not exceed 8 %. The results of the SPE-HPLC online method were further compared to results obtained by liquid&–liquid extraction with stable isotope dilution analysis LC-MS/MS and found to be in good agreement. The developed SPE-HPLC online system with fluorescence detection allows a reliable, accurate, and sensitive quantification (limit of quantification, 30 µg/kg) of ZEN in edible oils while significantly reducing the workload. To our knowledge, this is the first report on an automated SPE-HPLC method based on a covalent SPE approach. KW - Dynamic covalent hydrazine chemistry (DCHC) KW - Maize germ oil KW - Food KW - Mycotoxin KW - ZEA KW - Isomerisation KW - Occurrence KW - Edible oil KW - SIDA KW - LC-MS/MS KW - Quantification PY - 2015 U6 - https://doi.org/10.1007/s00216-015-8541-5 SN - 1618-2642 SN - 1618-2650 VL - 407 IS - 12 SP - 3489 EP - 3497 PB - Springer CY - Berlin AN - OPUS4-33067 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drzymala, Sarah A1 - Binder, J. A1 - Brodehl, Antje A1 - Penkert, M. A1 - Rosowski, M. A1 - Garbe, L.-A. A1 - Koch, Matthias T1 - Estrogenicity of novel phase I and phase II metabolites of zearalenone and cis-zearalenone N2 - Zearalenone and its cis-isomer, cis-zearalenone, are nonsteroidal mycotoxins that elicit an estrogenic response upon binding to the estrogen receptor. This study compares the estrogenicity of eleven congeners including novel metabolites as 15-OH-zearalenone, zearalenone-14-sulfate, α-cis-zearalenol and β-cis-zearalenol using the E-Screen assay. Overall, a change in the configuration from trans to cis retains significant estrogenic activity. In contrast, alterations of the aromatic moiety including hydroxylation and sulfation showed a markedly decreased estrogenicity when compared to zearalenone. KW - Zearalenone KW - Mycotoxin KW - MCF-7 KW - E-screen assay KW - Estrogenicity KW - Isomerization PY - 2015 U6 - https://doi.org/10.1016/j.toxicon.2015.08.027 SN - 0041-0101 SN - 1879-3150 VL - 105 SP - 10 EP - 12 PB - Elsevier CY - Oxford [u.a.] AN - OPUS4-34167 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Oberleitner, Lidia A1 - Eremin, S.A. A1 - Lehmann, Andreas A1 - Garbe, L.-A. A1 - Schneider, Rudolf T1 - Fluorescence polarization immunoassays for carbamazepine - comparison of tracers and formats N2 - For the antiepileptic drug and anthropogenic marker carbamazepine (CBZ), a fast and cost-effective immunoassay based on fluorescence polarization (FPIA) was developed. The required fluorophore conjugates were synthesized from different fluorescein and CBZ derivatives. The most suitable tracer was CBZ–triglycine–5-(aminoacetamido)fluorescein. Additionally, the applicability of the assay in tubes and on microtiter plates was tested. The first format can be performed in a portable instrument and therefore can be applied in field measurements. The measurement of an individual sample can be carried out within 4 min. This assay shows a measurement range of 2.5–1000 µg L-1 and a test midpoint (or IC50) of 36 µg L-1. The FPIA performed on microtiter plates is useful for the assay development and is suitable for a very high throughput (up to 24 samples in 20 min). The test midpoint of this assay is 13 µg L-1 and the measurement range is 1.5–300 µg L-1. Furthermore, this assay requires smaller sample volumes and less reagents, including the crucial amount of antibody. The applicability of both assays to spiked surface water samples was evaluated. The recovery rates vary between 66–110% on microtiter plates and 81–140% in tubes. PY - 2015 U6 - https://doi.org/10.1039/c5ay00617a SN - 1759-9660 SN - 1759-9679 VL - 7 IS - 14 SP - 5854 EP - 5861 PB - RSC Publ. CY - Cambridge AN - OPUS4-33821 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Stephan A1 - Hanelt, S. A1 - Canitz, C. A1 - Hoffmann, Holger A1 - Garbe, L.-A. A1 - Schneider, Rudolf T1 - Entwicklung monoklonaler Antikörper gegen Diclofenac N2 - Diclofenac (DCF) wird als nicht-steroidales, antientzündliches Arzneimittel gegen Fieber, Entzündungen, rheumatische Erkrankungen und Schmerzen eingesetzt. 70 % werden nach Einnahme wieder ausgeschieden. Aufgrund unvollständiger Elimination in den Kläranlagen lassen sich Rückstände im Trinkwasser und im Oberflächengewässer nachweisen. Diclofenac wird in der Umweltanalytik v.a. mittels GC-MS oder LCMS nachgewiesen. Bioanalytische Methoden machen sich die spezifische Antigen-Antikörper-Wechselwirkung zunutze, so z.B. Immunoassays. Die hierfür erforderlichen Antikörper werden durch Immunisierung mit einem Konjugat aus dem Analyten und einem Trägerprotein gewonnen. Die Kopplung kann direkt über die Carboxylfunktion von Diclofenac erfolgen. Um Abschirmungseffekte zu vermeiden, kann zwischen Protein und Analy1 ein Spacer sinnvoll sein. PY - 2015 SN - 1618-3258 SN - 1617-5301 IS - 4 SP - 107 EP - 109 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-35241 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -