TY - JOUR A1 - Knobbe, N. A1 - Vogl, Jochen A1 - Pritzkow, Wolfgang A1 - Panne, Ulrich A1 - Fry, H. A1 - Lochotzke, H.M. A1 - Preiss-Weigert, A. T1 - C and N stable isotope variation in urine and milk of cattle depending on the diet N2 - The stable carbon and nitrogen isotopic composition of urine and milk samples from cattle under different feeding regimes were analysed over a period of six months. The isotope ratios were measured with isotope ratio mass spectrometry (IRMS). The δ13C values of milk and urine were dependent on different feeding regimes based on C3 or C4 plants. The δ13C values are more negative under grass feeding than under maize feeding. The δ13C values of milk are more negative compared to urine and independent of the feeding regime. Under grass feeding the analysed milk and urine samples are enriched in 13C relative to the feed, whereas under maize feeding the 13C/12C ratio of urine is in the same range and milk is depleted in 13C relative to the diet. The difference between the 15N/14N ratios for the two feeding regimes is less pronounced than the 13C/12C ratios. The δ15N values in urine require more time to reach the new equilibrium, whereas the milk samples show no significant differences between the two feeding regimes. KW - Cattle KW - Urine KW - Milk KW - Feeding regime KW - Stable isotope PY - 2006 U6 - https://doi.org/10.1007/s00216-006-0644-6 SN - 1618-2642 SN - 1618-2650 VL - 386 IS - 1 SP - 104 EP - 108 PB - Springer CY - Berlin AN - OPUS4-12746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Leiterer, Jork A1 - Leitenberger, W. A1 - Emmerling, Franziska A1 - Thünemann, Andreas A1 - Panne, Ulrich T1 - The use of an acoustic levitator to follow crystallization in small droplets by energy-dispersive X-ray diffraction N2 - For the investigation of small sample volumes, the use of an acoustic levitator was tested as a `sample holder' for hovering droplets in a synchrotron beam. It might be advantageous to use levitated droplets instead of samples confined in solid holders, especially for the study of crystallization processes where the influence of containing walls has to be minimized. In a first experiment, the crystallization of sodium chloride in a small droplet of aqueous solution has been followed with a time resolution of 30 s. The collected diffraction peaks are compared with data in the ICSD database. KW - EDXD KW - Noncontact measurement technique KW - X-ray-scattering KW - Synchrotron-radiation KW - Acoustic levitation PY - 2006 U6 - https://doi.org/10.1107/S0021889806024915 SN - 0021-8898 SN - 1600-5767 VL - 39 IS - 5 SP - 771 EP - 773 PB - Blackwell CY - Oxford AN - OPUS4-13516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krause, Benjamin Christoph A1 - Seifert, Stephan A1 - Panne, Ulrich A1 - Kneipp, Janina A1 - Weidner, Steffen T1 - Matrix-assisted laser desorption/ionization mass spectrometric investigation of pollen and their classification by multivariate statistics N2 - RATIONALE A fast and reliable online identification of pollen is not yet available. The identification of pollen is based mainly on the evaluation of morphological data obtained by microscopic methods. METHODS Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) was applied to the analysis of extracts and milled pollen samples. The obtained MALDI data were explored for characteristic peak patterns which could be subjected to a multivariate statistical analysis. RESULTS Two sample preparation methods are presented, which require only minimal or no chemical extraction of the pollen. MALDI pollen spectra could be recorded showing various peak patterns. A multivariate statistics approach allowed the classification of pollen into clusters indicating similarities and differences between various species. CONCLUSIONS These results demonstrate the potential and the reliability of MALDI-TOF MS for the identification and, in combination with multivariate statistics, also for the classification of pollen. KW - MALDI TOF mass spectrometry KW - Pollen KW - Multivariate statistics PY - 2012 U6 - https://doi.org/10.1002/rcm.6202 SN - 0951-4198 SN - 1097-0231 VL - 26 IS - 9 SP - 1032 EP - 1038 PB - Wiley CY - Chichester AN - OPUS4-25648 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Würth, Christian A1 - González, M.G. A1 - Niessner, R. A1 - Panne, Ulrich A1 - Haisch, C. A1 - Resch-Genger, Ute T1 - Determination of the absolute fluorescence quantum yield of rhodamine 6G with optical and photoacoustic methods - providing the basis for fluorescence quantum yield standards N2 - To establish the methodical basis for the development and certification of fluorescence quantum yield standards, we determined the fluorescence quantum yield Φf of rhodamine 6G (R6G) with two absolute methods with complementary measurement principles, here optical spectroscopy using an integrating sphere setup and pulsed laser photoacoustic spectroscopy (PAS). For the assessment of aggregation- and reabsorption-induced distortions of measured fluorescence quantum yields and procedures for the reliable consideration of such effects, this systematic comparison was performed in ethanol and in water employing different concentrations of R6G. In addition, the relative and absolute fluorescence quantum yields of these solutions were obtained with a calibrated spectrofluorometer and a commercialized integrating sphere setup. Based upon this systematic comparison, experimental advantages and systematic sources of variation were identified for both methods. KW - Fluorescence KW - Photoluminescence KW - Quantum yield KW - Photoacoustic spectroscopy KW - Absolute quantum yield KW - Integrating sphere KW - Rhodamine 6G KW - Aggregation KW - Reabsorption PY - 2012 U6 - https://doi.org/10.1016/j.talanta.2011.12.051 SN - 0039-9140 VL - 90 SP - 30 EP - 37 PB - Elsevier CY - Amsterdam AN - OPUS4-25710 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schenk, Jonas A1 - Batzdorf, Lisa A1 - Emmerling, Franziska A1 - Kneipp, Janina A1 - Panne, Ulrich A1 - Buurman, Merwe T1 - Simultaneous UV/Vis spectroscopy and surface enhanced raman scattering of nanoparticle formation and aggregation in levitated droplets N2 - The formation and growth of hydroxylamine reduced silver nanoparticles were investigated by simultaneous Raman and UV/Vis spectroscopy coupled to an acoustic levitator as a sample holder. Based on the UV/Vis spectra, a two step particle formation mechanism with fast initial formation and adjacent coalescence can be proposed for the reduction of silver nitrate with hydroxylamine. The presence of the analyte adenine during particle formation resulted in differences in the adenine SERS signature compared to experiments, where adenine was added after particle synthesis. It was possible to monitor the adenine and sodium chloride induced aggregation of the nanoparticles and its dynamics based on both the extinction spectra and the SERS data. Correlating the information from the extinction spectra with the SERS intensity, the maximum SERS signals were observed at maximum extinction of the aggregated nanoparticle solution at the Raman excitation wavelength. PY - 2012 U6 - https://doi.org/10.1039/c2ay05744a SN - 1759-9660 SN - 1759-9679 N1 - Geburtsname von Batzdorf, Lisa: Tröbs, L. - Birth name of Batzdorf, Lisa: Tröbs, L. N1 - Geburtsname von Buurman, Merwe: Albrecht, M. - Birth name of Buurman, Merwe: Albrecht, M. VL - 4 IS - 5 SP - 1252 EP - 1258 PB - RSC Publ. CY - Cambridge AN - OPUS4-25742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bahlmann, Arnold A1 - Carvalho, José Joao A1 - Weller, Michael G. A1 - Panne, Ulrich A1 - Schneider, Rudolf T1 - Immunoassays as high-throughput tools: monitoring spatial and temporal variations of carbamazepine, caffeine and cetirizine in surface and wastewaters N2 - Carbamazepine (CBZ), caffeine and cetirizine were monitored by enzyme-linked immunosorbent assays (ELISAs) in surface and wastewaters from Berlin, Germany. This fast and cost-efficient method enabled to assess the spatial and temporal variation of these anthropogenic markers in a high-throughput screening. CBZ and cetirizine were detected by the same antibody, which selectively discriminates between both compounds depending on the pH value used in the incubation step. To our best knowledge, this is the first dual-analyte immunoassay working with a single antibody. The frequent sampling with 487 samples being processed allowed for the repeated detection of unusually high concentrations of CBZ and caffeine. ELISA results correlate well with the ones obtained by liquid chromatography tandem mass spectrometry (LC-MS/MS). Caffeine concentrations found in surface waters were elevated by combined sewer overflows after stormwater events. During the hay fever season, the concentrations of the antihistamine drug cetirizine increased in both surface and wastewaters. Caffeine was almost completely removed during wastewater treatment, while CBZ and cetirizine were found to be more persistent. The maximum concentrations of caffeine, CBZ and cetirizine found in influent wastewater by LC–MS/MS were 470, 5.0 and 0.49 µg L-1, while in effluent wastewater the concentrations were 0.22, 4.5 and 0.51 µg L-1, respectively. For surface waters, concentrations up to 3.3, 4.5 and 0.72 µg L-1 were found, respectively. KW - ELISA KW - Carbamazepine KW - Caffeine KW - Cetirizine KW - Environmental monitoring KW - Anthropogenic markers PY - 2012 U6 - https://doi.org/10.1016/j.chemosphere.2012.05.020 SN - 0045-6535 SN - 0366-7111 VL - 89 IS - 11 SP - 1278 EP - 1286 PB - Elsevier Science CY - Kidlington, Oxford AN - OPUS4-26187 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lindner, Uwe A1 - Lingott, Jana A1 - Richter, Silke A1 - Jakubowski, Norbert A1 - Panne, Ulrich T1 - Speciation of gadolinium in surface water samples and plants by hydrophilic interaction chromatography hyphenated with inductively coupled plasma mass spectrometry N2 - Hydrophilic interaction chromatography (HILIC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was optimized for speciation analysis of gadolinium-based contrast agents in environmental samples, in particular surface river waters and plants. Surface water samples from the Teltow channel, near Berlin, were investigated over a distance of 5 km downstream from the influx of a wastewater treatment plant. The total concentration of gadolinium increased significantly from 50 to 990 ngL-1 due to the influx of the contrast agents. After complete mixing with the river water, the concentration remained constant over a distance of at least 4 km. Two main substances [Dotarem® (Gd-DOTA) and Gadovist® (Gd-BT-DO3A)] have been identified in the river water using standards. A gadolinium-based contrast agent, possibly Gd-DOTA (Dotarem®), was also detected in water plant samples taken from the Teltow channel. Therefore, uptake of contrast agents [Gadovist® (Gd-BTDO3A), Magnevist® (Gd-DTPA), Omniscan® (Gd-DTPA-BMA), Dotarem® (Gd-DOTA), and Multihance® (Gd-BOPTA)] by plants was investigated in a model experiment using Lepidium sativum (cress plants). HILIC–ICP-MS was used for identification of different contrast agents, and a first approach for quantification using aqueous standard solutions was tested. For speciation analysis, all investigated contrast agents could be extracted from the plant tissues with a recovery of about 54 % for Multihance® (Gd-BOPTA) up to 106 % for Gadovist® (Gd-BT-DO3A). These experiments demonstrate that all contrast agents investigated are transported from the roots to the leaves where the highest content was measured. KW - Gadolinium-based contrast agents KW - Hydrophilic interaction chromatography (HILIC) KW - Speciation KW - Inductively coupled plasma mass spectrometry (ICP-MS) KW - Plants KW - Surface water PY - 2013 U6 - https://doi.org/10.1007/s00216-012-6643-x SN - 1618-2642 SN - 1618-2650 VL - 405 IS - 6 SP - 1865 EP - 1873 PB - Springer CY - Berlin AN - OPUS4-27929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gopala, Anil A1 - Mahn, S. A1 - Panne, Ulrich A1 - Kipphardt, Heinrich T1 - In situ vacuum thermal mass spectroscopy for the selection of an environmentally friendly, energy saving catalytic additive and optimization of the process by a novel ignition mechanism N2 - We report herein the utilization of vacuum thermal mass spectrometry (VTMS) for the selection of an environmentally friendly, energy saving catalytic additive and a novel ignition mechanism, which is complementary to catalysis for the reduction of zinc oxide with carbon. PY - 2013 U6 - https://doi.org/10.1039/c3ra40223a SN - 2046-2069 VL - 3 IS - 25 SP - 9677 EP - 9680 PB - RSC Publishing CY - London AN - OPUS4-28659 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhu, Shengchao A1 - Panne, Ulrich A1 - Rurack, Knut T1 - A rapid method for the assessment of the surface group density of carboxylic acid-functionalized polystyrene microparticles N2 - Particle-based assays are becoming versatile analytical tools due to their cost-effectiveness, speed, straightforward and diverse functionalization chemistries, especially when polystyrene particles are used. The introduction of functional groups (–COOH, –NH2, etc.) to the surface of such polystyrene particles promotes their application in bioanalytics. However, the traditional method to determine the amount of surface carboxylate groups is conductivity titration, which is usually time- and resources-consuming and discontinuous. Here, we synthesized polystyrene microparticles with different contents of carboxylate groups, and then investigated a simpler and potentially continuous approach to determine the amount of surface carboxylate groups by Zeta potential measurements. The results were compared to the traditional titration method and to actual coupling efficiencies of the functionalized particles with a model oligonucleotide probe as determined by flow cytometry. All quantification methods revealed good agreement. KW - Konduktometrische Titration KW - Mikropartikel KW - Oberflächenfunktionalisierung KW - Polystyrol KW - Zeta-Potential PY - 2013 U6 - https://doi.org/10.1039/c3an36578f SN - 0003-2654 SN - 1364-5528 VL - 138 IS - 10 SP - 2924 EP - 2930 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-28660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidner, Steffen A1 - Knappe, Patrick A1 - Panne, Ulrich T1 - MALDI-TOF imaging mass spectrometry of artifacts in 'dried droplet' polymer samples N2 - Matrix-assisted laser desorption/ionization-timeof-flight (MALDI-TOF) imaging of polystyrenes with various molecular masses was applied to study spatial molecular mass distribution of polymers in sample spots prepared by the 'dried droplet' method. When different solvents and target surfaces were examined, a segregation of single homologous polymers was observed depending upon the evaporation rate of the solvent. For the observed Patterns left by the evaporating droplet, a hypothesis is offered taking into account different hydrodynamic interactions and diffusion. The results illustrate that spot preparation using the conventionally 'dried droplet' method is prone to artifacts and should be avoided for reliable and reproducible MALDI mass spectrometry experiments with regards to the Determination of molecular masses and mass distributions. KW - MALDI KW - Mass spectrometry imaging KW - Polymer KW - Droplet PY - 2011 U6 - https://doi.org/10.1007/s00216-011-4773-1 SN - 1618-2642 SN - 1618-2650 VL - 401 IS - 1 SP - 127 EP - 134 PB - Springer CY - Berlin AN - OPUS4-24538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -