TY - GEN A1 - Hoffmann, Katrin A1 - Mix, Renate A1 - Friedrich, Jörg Florian A1 - Resch-Genger, Ute ED - Geddes, C.D. T1 - Spectroscopic characterization of plasma - Chemically functionalized and fluorophore-labeled polymer surfaces N2 - The potential of spectrofluorometry and fluorescence microscopy for the characterization and quantification of different functionalities like OH and NH2 groups at plasma-chemically modified polymer surfaces is assessed using traditional reactive dyes such as dansyl derivatives and a sophisticated VIS-excitable chromogenic and fluorogenic pyrylium label showing binding-induced spectral and intensity changes in absorption and emission. Aiming at an improved fluorometric surface analysis, based upon these measurements, several sources of uncertainty inherent to fluorescence measurements are illustrated ranging from environment-dependent dye absorption and emission features over spectral correction and nonspecific adsorption to the critical influence of label choice on the measured background. Solutions to these drawbacks are given thereby underlining the potential of fluorometry for surface analysis. KW - Polymer functionalization KW - Plasma modification KW - Fluorescence spectroscopy KW - Surface labeling PY - 2010 SN - 978-1-4419-0828-5 U6 - https://doi.org/10.1007/978-1-4419-1260-2_6 N1 - Serientitel: Reviews in Fluorescence – Series title: Reviews in Fluorescence VL - 5 SP - 139 EP - 160 PB - Springer Science + Business Media AN - OPUS4-21274 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Würth, Christian A1 - Lochmann, Cornelia A1 - Spieles, Monika A1 - Pauli, Jutta A1 - Hoffmann, Katrin A1 - Schüttrigkeit, T. A1 - Franzl, T. A1 - Resch-Genger, Ute T1 - Evaluation of a commercial integrating sphere setup for the determination of absolute photoluminescence quantum yields of dilute dye solutions N2 - The commercial availability of stand-alone setups for the determination of absolute photoluminescence quantum yields (φf) in conjunction with the increasing use of integrating sphere accessories for spectrofluorometers is expected to have a considerable influence not only on the characterization of chromophore systems for use in optical and opto-electronic devices, but also on the determination of this key parameter for (bio)analytically relevant dyes and functional luminophores. Despite the huge potential of systems measuring absolute φf values and the renewed interest in dependable data, evaluated protocols for even the most elementary case, the determination of the fluorescence quantum yield of transparent dilute solutions of small organic dyes with integrating sphere methods, are still missing. This encouraged us to evaluate the performance and sources of uncertainty of a simple commercial integrating sphere setup with dilute solutions of two of the best characterized fluorescence quantum yield standards, quinine sulfate dihydrate and rhodamine 101, strongly differing in spectral overlap between absorption and emission. Special attention is dedicated to illustrate common pitfalls of this approach, thereby deriving simple procedures to minimize measurement uncertainties and improve the comparability of data for the broad community of users of fluorescence techniques. KW - Lifetime KW - Fluorescence KW - Luminescence KW - Quantum yield KW - Quantum efficiency KW - Integrating sphere KW - Reabsorption KW - Rhodamine 101 KW - Quinine sulfate dihydrate KW - Method KW - Photoluminescence KW - Standard KW - Emission KW - Spectral correction KW - Excitation KW - Anisotropy PY - 2010 U6 - https://doi.org/10.1366/000370210791666390 SN - 0003-7028 SN - 1943-3530 VL - 64 IS - 7 SP - 733 EP - 741 PB - Society for Applied Spectroscopy CY - Frederick, Md. AN - OPUS4-22089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hoffmann, Katrin A1 - Behnke, Thomas A1 - Resch-Genger, Ute T1 - Lifetime-based Discrimination Between Spectrally Matching vis and NIR Emitting Particle Labels and Probes T2 - 16th International Workshop on "Single Molecule Spectroscopy and Ultra Sensitive Analysis in the Life Sciences" CY - Berlin, Germany DA - 2010-09-15 PY - 2010 AN - OPUS4-22084 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Resch-Genger, Ute A1 - Hoffmann, Katrin A1 - Würth, Christian A1 - Behnke, Thomas A1 - Hoffmann, Angelika A1 - Pfeifer, Dietmar A1 - Engel, A. T1 - The toolbox of fluorescence standards: Flexible calibration tools for the standardization of fluorescence-based measurements N2 - To improve the reliability of fluorescence data in the life and material sciences and to enable accreditation of fluorescence techniques, standardization concepts are required that guarantee and improve the comparability of fluorescence measurements. At the core of such concepts are simple and evaluated fluorescence standards for the consideration of instrument-specific spectral and intensity distortions of measured signals and for instrument performance validation (IPV). Similarly in need are fluorescence intensity standards for the quantification from measured intensities and for signal referencing, thereby accounting for excitation light-induced intensity fluctuations. These standards should be preferably certified, especially for use in regulated areas like medical diagnostics. This encouraged us to develop liquid and solid standards for different fluorescence parameters and techniques for use under routine measurement conditions in different formates. Special emphasis was dedicated to the determination and control of the spectral responsivity of detection systems, wavelength accuracy, homogeneity of illumination, and intensity referencing for e.g. spectrofluorometers, fluorescence sensors and confocal laser scanning fluorescence microscopes. Here, we will present design concepts and examples for mono- and multifunctional fluorescence standards that provide traceability to radiometric units and present a first step towards a toolbox of standards. KW - Fluorescence KW - Fluorescence standard KW - Calibration tool KW - Spectral fluorescence standard KW - Intensity standard KW - Instrument performance validation KW - Quality assurance KW - Traceability KW - Glass KW - Liquid standard PY - 2010 U6 - https://doi.org/10.1117/12.853133 SN - 0277-786X SN - 0038-7355 SN - 0361-0748 VL - 7666 IS - 76661J SP - 1 EP - 12 PB - Soc. CY - Redondo Beach, Calif. [u.a.] AN - OPUS4-21595 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hoffmann, Katrin A1 - Sewohl, Dirk A1 - Resch-Genger, Ute T1 - Evaluation of Lanthanide-doped Glasses for Use as standards in Fluorometry T2 - First International Conference on Luminescence of Lanthanides CY - Odessa, Ukraine DA - 2010-09-05 PY - 2010 AN - OPUS4-21566 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -