TY - CONF A1 - Engel, A. A1 - Ottermann, C. A1 - Klahn, J. A1 - Korb, T. A1 - Resch-Genger, Ute A1 - Hoffmann, Katrin A1 - Kynast, U. A1 - Rupertus, V. ED - Dan V. Nicolau, ED - Daniel L. Farkas, ED - Robert C. Leif, T1 - Anorganic fluorescence reference materials for decay time of fluorescence emission T2 - Imaging, manipulation, and analysis of biomolecules, cells, and tissues VI (Proceedings of SPIE) N2 - Fluorescence techniques are known for their high sensitivity and are widely used as analytical tools, detection methods and imaging applications for product and process control, material sciences, environmental and bio-technical analysis, molecular genetics, cell biology, medical diagnostics, and drug screening. According to DIN/ISO 17025 certified standards are used for steady state fluorescence diagnostics, a method having the drawback of giving relative values for fluorescence intensities only. Therefore reference materials for a quantitative characterization have to be related directly to the materials under investigation. In order to evaluate these figures it is necessary to calculate absolute numbers such as absorption/excitation cross sections and quantum yield. This has been done for different types of dopands in different materials such as glass, glass ceramics, crystals or nano crystalline material embedded in polymer matrices. Samples doped with several fluophores of different emission wavelengths and decay times are required for fluorescent multiplexing applications. Decay times shorter than 100 ns are of special interest. In addition, a proper knowledge is necessary of quantum efficiency in highly scattering media. Recently, quantum efficiency in YAG:Ce glass ceramics has been successfully investigated. Glass and glass ceramics doped with threefold charged rare earth elements are available. However, these samples have the disadvantage of emission decay times much longer than 1 microsecond, due to the excitation and emission of their optical forbidden electronic transitions. Therefore first attempts have been made to produce decay-time standards based on organic and inorganic fluophores. Stable LUMOGEN RED pigments and YAG:Ce phosphors are diluted simultaneously in silicone matrices using a wide range of concentrations between 0.0001 and 2 wt%. Organic LUMOGEN RED has decay times in the lower nanosecond range with a slight dependency on concentration and temperature. In addition, the well-known decay properties of inorganic YAG:Ce are observed also embedded in silicone matrix. Luminescent silicone layers are obtained with thicknesses between 150 and 300 m and no change of decay time, which has been determined to be between 60 and 62 ns. Finally, first results are shown for fluorescent CaF2:Pb glass ceramics embedded in a silicate glass matrix. Wavelength accuracy and lifetime are characterized for different environmental conditions such as temperature treatment and UV irradiation. Moreover, intensity patterns, e.g. line profiles and results, are discussed on homogeneity and photo and thermal stability, respectively. Fluorescence (steady state, decay time) and absorption (remission, absorption) spectroscopy are employed as diagnostic methods to get a microscopic view of the relevant physical processes. The work is funded by BMBF under project number 13N8849. KW - Fluorescence KW - Reference material KW - Glass KW - Glass ceramic KW - Phosphor KW - Doped glass and glass ceramics PY - 2008 SN - 978-0-8194-7034-8 DO - https://doi.org/10.1117/12.767633 VL - 6859 SP - 68591A-1 - 68591A-10 PB - SPIE, the International Society for Optical Engineering CY - Bellingham, Wash. AN - OPUS4-19800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Engel, A. A1 - Ottermann, C. A1 - Klahn, J. A1 - Enseling, D. A1 - Korb, T. A1 - Resch-Genger, Ute A1 - Hoffmann, Katrin A1 - Schweizer, S. A1 - Selling, J. A1 - Kynast, U. A1 - Koberling, F. A1 - Rupertus, V. T1 - Fluorescence reference materials used for optical and biophotonic applications JF - Proceedings of SPIE-OSA biomedical optics / Diagnostic optical spectroscopy in biomedicine IV N2 - Fluorescence techniques are known for their high sensitivity and are widely used as analytical tools and detection methods for product and process control, material sciences, environmental and bio-technical analysis, molecular genetics, cell biology, medical diagnostics, and drug screening. According to DIN/ISO 17025 certified standards are used for fluorescence diagnostics having the drawback of giving relative values for fluorescence intensities only. Therefore reference materials for a quantitative characterization have to be related directly to the materials under investigation. In order to evaluate these figures it is necessary to calculate absolute numbers like absorption/excitation cross sections and quantum yield. This can be done for different types of dopands in different materials like glass, glass ceramics, crystals or nano crystalline material embedded in polymer matrices. Based on the optical spectroscopy data we will discuss options for characteristic doped glasses and glass ceramics with respect to scattering and absorption regime. It has shown recently for YAG:Ce glass ceramics that for a proper determination of the quantum efficiency in these highly scattering media a reference material with similar scattering and fluorescent properties is required. This may be performed using the emission decay measurement diagnostics, where the decay time is below 100 ns. In this paper we present first results of these aspects using well performing LUMOGEN RED organic pigments for a comparison of mainly transparent glass with glass ceramics doped with various amounts of dopands e.g. ions of raw earth elements and transition metals. The LUMOGEN red is embedded in silica and polyurethane matrices. Characterisations on wavelength accuracy and lifetime for different environmental conditions (temperature, UV irradiation) have been performed. Moreover intensity patterns and results for homogeneity, isotropy, photo and thermal stability will be discussed. In a next step we will show the transfer of the characterisation methods to inorganic fluophores (YAG:Ce) in silicon. Fluorescence (steady state, decay time) and absorption (remission, absorption) spectroscopy working in different temperature regimes (10 - 350 K) are employed diagnostic methods in order to get a microscopic view of the relevant physical processes and to prove the correctness of the obtained data. The work is funded by BMBF under project number 13N8849. KW - Fluorescence KW - Reference material KW - Glass KW - Glass ceramic KW - Phosphor KW - Doped glass KW - Glass ceramics PY - 2007 SN - 0-8194-6247-0 DO - https://doi.org/10.1117/12.728144 SN - 1605-7422 VL - 6628 SP - 662815-1 - 662815-9 AN - OPUS4-16729 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Engel, A. A1 - Ottermann, C. A1 - Resch-Genger, Ute A1 - Hoffmann, Katrin A1 - Schweizer, S. A1 - Selling, J. A1 - Spaeth, J.-M. A1 - Rupertus, V. ED - Grzymala, R. ED - Haeberlé, O. T1 - Glass based fluorescence reference materials used for optical and biophotonic applications JF - Proceedings of SPIE - Biophotonics and new therapy frontiers N2 - Fluorescence techniques are known for their high sensitivity and are widely used as analytical tools and detection methods for product and process control, material sciences, environmental and biotechnical analysis, molecular genetics, cell biology, medical diagnostics, and drug screening. For routine measurements by fluorescence techniques the existence of an improved quality assurance is one of the basic needs. According to DIN/ISO 17025 certified standards are used for fluorescence diagnostics having the drawback of giving relative values only. Typical requirements onto fluorescence reference materials or standards deal with the verification of the instrument performance as well as the improvement of the data comparability. Especially for biomedical applications fluorescence labels are used for the detection of proteins. In particular these labels consist of nano crystalline materials like CdS and CdSe. The field of Non-Cadmium containing materials is under investigation. In order to evaluate whether glass based materials can be used as standards it is necessary to calculate absolute values like absorption/excitation cross sections or relative quantum yields. This can be done using different quantities of dopands in glass, glass ceramics or crystals. The investigated materials are based on different types of glass, silicate, phosphate and boron glass, which play a dominant role for the absorption and emission mechanism. Additional to the so-called elementary fluorescence properties induced by raw earth elements the formation of defects lead to higher cross sections additionally. The main investigations deal with wavelength accuracy and lifetime of doped glasses, glass ceramics and crystalline samples. Moreover intensity patterns, homogeneity aspects and photo stability will be discussed. KW - Fluorescence KW - Reference material KW - Glass KW - Glass ceramics KW - Biophotonic KW - Multiplexing PY - 2006 DO - https://doi.org/10.1117/12.663627 SN - 1605-7422 VL - 6191 SP - 619110-1-619110-10 AN - OPUS4-14429 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -