TY - CONF A1 - Resch-Genger, Ute A1 - Würth, Christian A1 - Frenzel, Florian A1 - Grauel, Bettina A1 - Nirmalananthan-Budau, Nithiya A1 - Pauli, Jutta A1 - Hoffmann, Katrin T1 - Photoluminescence at BAM – Photoluminescence at BAM – Photophysical Studies, Quantum Yield Measurements, Multiplexing Strategies, and Standards N2 - Photoluminescence applications in the life and material sciences require bright molecular and nanocrystalline emitters, stimuli-responsive optical probes, signal enhancement, multiplexing, and barcoding strategies and traceable methods to quantify the signal-relevant optical properties of luminescent materials at the ensemble and single molecule/particle level. In this context, current research at Division Biophotonics of BAM is presented ranging from dye and nanocrystal photophysics, absolute measurements of photoluminescence quantum yields in the UV/vis/NIR/SWIR, lifetime multiplexing, and the development of different types of fluorescence standards for validating optical-spectroscopic measurements. T2 - Institutskolloquium IPHT CY - Jena, Germany DA - 22.10.2019 KW - Surface group analysis KW - NIR KW - SWIR KW - Quantum dot KW - Lanthanide KW - Cleavable probe KW - Lifetime KW - Multiplexing KW - Sensor KW - Assay PY - 2019 AN - OPUS4-49360 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Advanced characterization of nanomaterials N2 - The rational synthesis and use of nanomaterials require the characterization of many different properties, ranging from particle size and size distribution over surface chemistry to more applicationrelevant features like optical, electrochemical, and magnetic properties. In the following, several methods for the characterization of functional groups on nanomaterials, like polymer and silica nanoparticles, semiconductor quantum dots, and lanthanide-based upconversion nanocrystals are presented. Additionally, procedures for the measurement of the key spectroscopic performance parameters of nanomaterials with linear and nonlinear photoluminescence, such as the photoluminescence quantum yield, are presented for the UV/vis/NIR/SWIR. T2 - Summerschool CY - Bad Honnef, Germany DA - 22.07.2019 KW - Quantum yield KW - Nanoparticle KW - Fluorescence KW - Quantum dot KW - NIR KW - SWIR KW - Quality assurance KW - Calibration PY - 2019 AN - OPUS4-48630 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Pauli, Jutta A1 - Würth, Christian A1 - Güttler, Arne A1 - Richter, Maria A1 - Schneider, Thomas T1 - Determining Photoluminescence Quantum Yields of Molecular and Nanocrystal Emitters in the UV/vis/NIR/SWIR N2 - The comparison of different emitter classes and the rational design of the next generation of molecular and nanoscale reporters require accurate and quantitative photo-luminescence measurements. This is of special importance for all photoluminescence applications in the life and material sciences and nanobiophotonics. In the following, procedures for the determination of the spectroscopic key parameter photoluminescence quantum yield, i.e., the number of emitted per absorbed photons, in the UV/vis/NIR/SWIR are presented including pitfalls and achievable uncertainties and material-specific effects related to certain emitter classes are addressed. T2 - Kolloqium National Center for Nanoscience and Technology CY - Peking, People's Republic of China DA - 18.10.2019 KW - Fluorescence KW - Quantum yield KW - Integrating sphere spectroscopy KW - Dye KW - Nanocrystal KW - NIR KW - SWIR KW - Quantum dot KW - Fluorescence standard KW - Uncertainty KW - Calibration PY - 2019 AN - OPUS4-49362 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Weigert, Florian A1 - Frenzel, Florian A1 - Würth, Christian A1 - Hoffmann, Katrin A1 - Martynenko, Irena A1 - Dhamo, Lorena T1 - Photoluminescence Properties of Different Types of Nanocrystals at the Ensemble and Single Emitter Level N2 - Correlating the photoluminescence (PL) properties of nanomaterials like semiconductor nanocrystals (QDs) and upconversion nanocrystals (UCNPs) assessed in ensemble studies and at the single particle level is increasingly relevant for applications of these nanomaterials in the life sciences like bioimaging studies or their use as reporters in microfluidic assays. Here we present a comparison of the spectroscopic properties of ensembles and single emitters for QDs like II/VI QDs and cadmium-free AIS/ZnS QDs as well as different UCNPs. The overall goal of this study was to derive particle architectures well suited for spectroscopic and microscopic applications. T2 - BIOSSPIE CY - San Francisco, CA, USA DA - 02.02.2019 KW - Quantum yield KW - Nanomaterial KW - Photoluminescence KW - Absolute fluorometry KW - Integrating sphere spectroscopy, KW - NIR KW - IR KW - Fluorescence KW - Nanoparticle KW - Semiconductor KW - Quantum dot KW - Single particle spectroscopy KW - Surface chemistry PY - 2019 AN - OPUS4-47358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Würth, Christian A1 - Kaiser, Martin A1 - Pauli, Jutta A1 - Hoffmann, Katrin T1 - Relative and Absolute Methods for Measuring Photoluminescence Quantum Yields of UV/vis/NIR Emitters N2 - One of the key spectroscopic performance parameters of molecular and particulate emitters is the photoluminescence quantum yield (PL QY) that provides a direct measure for the number of emitted per absorbed photons. This triggered the interest in methods suitable for measuring this property for emitters in various environments in the UV/vis/NIR and above 1000 nm as well as on the ensemble and single emitter level. Moreover, for nonlinear emitters like lanthanide-based upconversion nanocrystals methods including instrumentation for power density-dependent PL QY studies are required. An overview of the research activities in Division Biophotonics of BAM is given and suitable relative and absolute methods for the deter-mination of PL QY of organic dyes and different types of application-relevant nanomaterials in dispersion and in the solid state are presen-ted. This covers also the design and calibration of integrating sphere setups, achievable uncertainties, and candidates for PL QY reference materials. T2 - OSRAM Veranstaltung CY - Regensburg, Germany DA - 09.01.2019 KW - Quantum yield KW - Calibration KW - Reference material KW - Uncertainty KW - Absolute fluorometry KW - Integrating sphere spectroscopy KW - NIR KW - IR KW - Fluorescence KW - Nanoparticle KW - Dye PY - 2019 AN - OPUS4-47263 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Nirmalananthan-Budau, Nithiya A1 - Moser, Marko A1 - Roloff, Alexander A1 - Rühle, Bastian A1 - Borcherding, H. A1 - Thiele, T. A1 - Schedler, U. T1 - Cleavable probes and catch and release assays for surface group quantification on 2D- and 3D-supports N2 - Surface functionalization of 2D- and 3D-supports and nanomaterials are nowadays at the core of many applications of functional materials in the life and material sciences. Examples range from membranes and microarrays over bead-based assays, immunoseparation, and next generation sequencing to nanometer-sized optical reporters, nanosensors, and magnetic and optical contrast agents. Typically performed functionalization procedures include silanization and grafting reactions with reactive monomers to introduce functional groups like amino or carboxylic acid groups and the attachment of ligands like polyethylene glycol (PEG) molecules and biomolecules such as peptides, proteins, and DNA.[1-3] We present here a versatile concept to quantify the number of bioanalytically relevant functional groups like carboxyl, amino, and aldehyde moieties through the specific binding and subsequent release of small reporter molecules such as fluorescent dyes and non-fluorescent chromophores utilizing cleavable linkers or the formation of cleavable bonds as a reversible covalent labeling strategy. This is representatively demonstrated for different types of nano- and microparticles with different labeling densities of carboxyl, amino, and aldehyde groups. This strategy enables to separate the signal-generating molecule from the bead surface, thereby circumventing uncertainties associated with light scattering, binding-induced changes in reporter fluorescence, and fluorescence quenching dye-dye interactions on crowded material surfaces.[1-3] Moreover, the reporters are chosen to be detectable with different analytical methods as prerequisite for straightforward validation via method compari-sons and mass balances. Applications of these assays and multimodal cleavable probes range from a quantitative comparison of bead batches and process control to a qualitative prediction of the coupling efficiencies in bioconjugation reactions. T2 - ANAKON 2019 CY - Münster, Germany DA - 25.03.2019 KW - Nanoparticle KW - Surface group KW - Surface analysis KW - Cleavable probe KW - Optical assay KW - Quality assurance KW - Conductometry KW - Dye labeling KW - Methos comparision PY - 2019 AN - OPUS4-47628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Luminescence measurements, calibration strategies and photoluminescence quantum yields N2 - Different types of optical spectroscopies are introduced with special emphasis on method-inherent limitations and reliable instrument calibration and performance validation. In addition, procedures for the determination of spectroscopic key parameters like the photoluminescence quantum yield are presented including required instrument calibrations and material-specific effects related to certain emitters. T2 - Fakultät der University of Ottawa CY - Ottawa, Canada DA - 11.12.2018 KW - Quality assurcance KW - Optical spectroscopy KW - Method comparison KW - Photoluminescence KW - Calibration KW - Performance validation KW - Dye KW - Nanoparticle KW - Quantum dots KW - Quantum yields KW - Uncertainty KW - Method validation PY - 2019 AN - OPUS4-47630 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Agea-Blanco, Boris A1 - Blaeß, Carsten A1 - Waurischk, Tina T1 - Sintering and foaming of silicate glass powders N2 - Glass powders are promising candidates for manufacturing a broad diversity of sintered materials like sintered glass-ceramics, glass matrix composites, glass bonded ceramics or pastes. Powder processing, however, can substantially affect sinterability, e.g. by promoting surface crystallization. On the other hand, densification can be hindered by gas bubble formation for slow crystallizing glass powders. Against this background, we studied sintering and foaming of silicate glass powders with different crystallization tendency for wet milling and dry milling in air, Ar, N2, and CO2 by means of heating microscopy, DTA, Vacuum Hot Extraction (VHE), SEM, IR spectroscopy, XPS, and ToF-SIMS. In any case, foaming activity increased significantly with progressive milling. For moderately milled glass powders, subsequent storage in air could also promote foaming. Contrarily, foaming could be substantially reduced by milling in water and 10 wt% HCl. Although all powder compacts were uniaxially pressed and sintered in air, foaming was significantly affected by different milling atmosphere and was found most pronounced for milling in CO2 atmosphere. Conformingly, VHE studies revealed that foaming is mainly driven by carbonaceous species, even for powders milled in other gases. Current results of this study thus indicate that foaming is caused by carbonaceous species trapped on the glass powder surface. T2 - IMAPS/ACerS 15th International Conference and Exhibition on Ceramic Interconnect and Ceramic Microsystems Technologies (CICMT 2019) CY - Shanghai, China DA - 16.04.2019 KW - Glass powder KW - Sintering KW - Foaming PY - 2019 AN - OPUS4-48196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan A1 - Tielemann, Christopher A1 - Busch, R. A1 - Patzig, C. A1 - Müller, Ralf A1 - Höche, T. T1 - Oriented surface crystallization in 18BaO·22CaO·60SiO2 and MgO·CaO·2SiO2 glasses N2 - Up to now, oriented surface crystallization phenomena are discussed controversially, and related studies are restricted to few glasses. The vast majority of previous work does not consider possible effects of surface preparation and surrounding atmosphere. Moreover, very few observations of surface crystal orientation were made on separately grown crystals. The aim of our project is to advance the basic understanding of oriented surface crystallization, e.g. whether preferred orientation of surface crystals results from oriented nucleation or reorientation mechanisms during early crystal growth. In both cases, crystal orientation may reflect the orientation of the glass surface or that of anisotropic active surface nucleation sites. Therefore, we focus on orientation of surface crystals separately growing under controlled conditions. First results on diopside (MgCaSi2O6) and walstromite (BaCa2Si3O9) crystals growing from 18BaO·22CaO·60SiO2 and MgO·CaO·2SiO2 glass surfaces, respectively, indicate that different orientation mechanisms may occur. Neighbored walstromite crystals were found to gradually reorient themselves when they are going to impinge each other during stepwise isothermal treatments (log η = 4,5 Pa*s) of polished glass samples. Nevertheless, no preferred crystal orientation was evident for separate crystals. For diopside crystals growing from polished glass surfaces (1 μm diamond lapping foil), strong preferred orientation was observed for 3.5 to 85 min annealing at 850 °C. Electron Backscatter Diffraction (EBSD) studies showed that the c-axis of surface crystals is oriented parallel to the glass surface and that separated diopside crystals as small as 600 nm are already oriented. Studies on glass surfaces, polished with diamond lapping foils starting from 16 μm down to 1 μm grain, revealed that crystal orientation may scatter arround this preferential orientation and that this scatter progressively decreases with decreasing polishing grain size. T2 - 93rd Annual Meeting of the German Society of Glass Technology (DGG) in conjunction with the French Union for Science and Glass Technology (USTV) Annual Meeting CY - Nuremberg, Germany DA - 13.05.2019 KW - Surface crystallization KW - Orientation KW - Glass KW - Diopside PY - 2019 AN - OPUS4-48198 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Glass N2 - Überblick über die Arbeitsschwerpunkte des Fachbereichs 5.6 Glas und die Vielfalt des Werkstoffs Glas. An Hand der Vakuumheißgasextraktion (VHE) werden einige Beispiele u.a. zur Bestimmung des Wassergehalts oder des Diffusionskoeffizienten von Wasserstoff in Gläsern gezeigt. Zum Schluss erfolgt ein Ausblick auf die im nächsten Jahr zur Verfügung stehende robotergestützte Glasscreening Anlage. N2 - Overview about the key activities of division 5.6 glass and the diversity of the material glass. For the vacuum hot extraction method (VHE-MS) some examples are presented e. g. for the measurement of water content or the determination of diffusion coefficient of hydrogen in glasses. Finally, an outlook is shown on the robot controlled glass screening device which will be available next year. T2 - BAM - IFW Workshop CY - Berlin, Germany DA - 25.11.2019 KW - Glass KW - Glass screening device KW - Vacuum hot extraction PY - 2019 AN - OPUS4-50452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -