TY - JOUR A1 - Schmidt, Stephan A1 - Hoffmann, Holger A1 - Garbe, L.-A. A1 - Schneider, Rudolf T1 - Liquid chromatography-tandem mass spectrometry detection of diclofenac and related compounds in water samples N2 - A frequently studied environmental contaminant is the active substance diclofenac, which is removed insufficiently in sewage treatment plants. Since its inclusion in the watch list of the EU Water Framework Directive, the concentrations in surface waters will be determined throughout Europe. For this, still, more precise analytical methods are needed. As a reference, HPLC-MS is frequently employed. One of the major metabolites is 4’-hydroxydiclofenac (4’-OH-DCF). Also, diclofenac lactam is important for assessing degradation and transformation. Aceclofenac (ACF), the glycolic acid ester of diclofenac is used as a drug, too, and could potentially be cleaved to yield diclofenac again. In various sewage treatment plant influent samples, diclofenac, 4’-OH-DCF, DCF lactam and ACF could be determined with detection limits of 3 µg/L, 0.2 µg/L, 0.17 µg/L and 10 ng/L, respectively. KW - Diclofenac KW - Festphasenextraktion KW - HPLC-MS KW - Probenvorbereitung KW - Kläranlage KW - Abwasser KW - Zyklisierung KW - Diclofenac KW - Solid-phase extraction KW - Sewage treatment plant KW - Cyclization KW - Sample treatment KW - HPLC–MS PY - 2018 U6 - https://doi.org/10.1016/j.chroma.2018.01.037 SN - 0021-9673 SN - 1873-3778 VL - 1538 SP - 112 EP - 116 PB - Elsevier B.V. CY - Amsterdam, NL AN - OPUS4-44183 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baldofski, Stefanie A1 - Hoffmann, Holger A1 - Lehmann, Andreas A1 - Breitfeld, Stefan A1 - Garbe, L.-A. A1 - Schneider, Rudolf T1 - Enzyme-linked immunosorbent assay (ELISA) for the anthropogenic marker isolithocholic acid in water N2 - Bile acids are promising chemical markers to assess the pollution of water samples with fecal material. This study describes the optimization and validation of a direct competitive enzyme-linked immunosorbent assay for the bile acid isolithocholic acid (ILA). The quantification range of the optimized Assay was between 0.09 and 15 mg/L. The assay was applied to environmental water samples. Most studies until now were focused on bile acid fractions in the particulate phase of water samples. In order to avoid tedious sample preparation, we undertook to evaluate the dynamics and significance of ILA levels in the aqueous phase. Very low concentrations in tap and surface water samples made a pre-concentration step necessary for this matrix as well as for wastewater treatment plant (WWTP) effluent. Mean recoveries for spiked water samples were between 97% and 109% for tap water and WWTP influent samples and between 102% and 136% for WWTP effluent samples. 90th percentiles of intra-plate and inter-plate coefficients of variation were below 10% for influents and below 20% for effluents and surface water. ILA concentrations were quantified in the range of 33-72 mg/L in influent, 21-49 ng/L in effluent and 18-48 ng/L in surface water samples. During wastewater Treatment the ILA levels were reduced by more than 99%. ILA concentrations of influents determined by ELISA and LC-MS/MS were in good agreement. However, findings in LC-ELISA experiments suggest that the true ILA levels in concentrated samples are lower due to interfering effects of matrix compounds and/or cross-reactants. Yet, the ELISA will be a valuable tool for the performance check and comparison of WWTPs and the localization of fecal matter input into surface waters. KW - ELISA KW - LC-MS/MS KW - Bile acids KW - Fecal marker KW - Surface water KW - Wastewater PY - 2016 U6 - https://doi.org/10.1016/j.jenvman.2016.08.023 SN - 0301-4797 VL - 182 SP - 612 EP - 619 AN - OPUS4-37668 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 -