TY - JOUR A1 - Resch-Genger, Ute A1 - Hoffmann, Katrin A1 - Nietfeld, W. A1 - Engel, A. A1 - Neukammer, J. A1 - Nitschke, R. A1 - Ebert, B. A1 - Macdonald, R. T1 - How to Improve Quality Assurance in Fluorometry: Fluorescence-Inherent Sources of Error and Suited Fluorescence Standards N2 - The scope of this paper is to illustrate the need for an improved quality assurance in fluorometry. For this purpose, instrumental sources of error and their influences on the reliability and comparability of fluorescence data are highlighted for frequently used photoluminescence techniques ranging from conventional macro- and microfluorometry over fluorescence microscopy and flow cytometry to microarray technology as well as in vivo fluorescence imaging. Particularly, the need for and requirements on fluorescence standards for the characterization and performance validation of fluorescence instruments, to enhance the comparability of fluorescence data, and to enable quantitative fluorescence analysis are discussed. Special emphasis is dedicated to spectral fluorescence standards and fluorescence intensity standards. KW - Fluorescence KW - Standard KW - Calibration KW - Microarray KW - In vivo imaging KW - Flow cytometry PY - 2005 U6 - https://doi.org/10.1007/s10895-005-2630-3 SN - 1053-0509 SN - 1573-4994 VL - 15 IS - 3 SP - 337 EP - 362 PB - Plenum Publ. Corp. CY - New York, NY AN - OPUS4-10823 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voigt, J. A1 - Ebert, B. A1 - Hoffmann, Angelika A1 - Macdonald, R. T1 - Validierung eines "Fluorescent Enzyme Linked Immunosorbent Assay" (ELISA) N2 - Immunologische Verfahren haben während der vergangenen Jahrzehnte eine große Verbreitung in der Medizin gefunden. Grundlage dieser Verfahren ist die spezifische Bindung zwischen Antigen und Antikörper. Eine der wichtigsten Methoden zum sensitiven und quantitativen Nachweis biologisch relevanter Moleküle ist hierbei der Enzyme Linked Immunosorbent Assay (ELISA). Unter dem Aspekt der zahlreichen Einsatzgebiete ist die Frage nach Messunsicherheiten bei der Konzentrationsbestimmung von Biomolekülen mittels ELISA aus metrologischer Sicht von großem Interesse. Eine erhebliche Herausforderung stellt hierbei die Vielzahl von Einflussgrößen dar, die zudem hinsichtlich ihrer Messunsicherheit nur schwer zu quantifizieren sind. In Hinblick auf den Einsatz der Assays im Bereich der Laboratoriumsmedizin besteht die Notwendigkeit, Genauigkeit und Zuverlässigkeit dieser Messverfahren zu validieren. Zu diesem Zwecke wurden im Rahmen einer CCQM-Studie (CCQM- Comité consultatif pour la quantité de matiè re - métrologie en chimie ) internationale Vergleichsmessungen an einem ELISA zur Zytokinbestimmung (humanes Interferon-a) durchgeführt, an denen sich die PTB beteiligt hat. KW - ELISA KW - Interferon-Alpha KW - Metrologie KW - CCQM-Studie PY - 2008 SN - 0030-834X VL - 118 IS - 4 SP - 255 EP - 260 PB - Wirtschaftsverl. NW CY - Bremerhaven AN - OPUS4-22690 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Resch-Genger, Ute A1 - Bremser, Wolfram A1 - Pfeifer, Dietmar A1 - Spieles, Monika A1 - Hoffmann, Angelika A1 - DeRose, P.C. A1 - Zwinkels, J. C. A1 - Gauthier, F. A1 - Ebert, B. A1 - Taubert, R.D. A1 - Voigt, J. A1 - Hollandt, J. A1 - Macdonald, R. T1 - State-of-the art comparability of corrected emission spectra. 2. Field laboratory assessment of calibration performance using spectral fluorescence standards N2 - In the second part of this two-part series on the state-of-the-art comparability of corrected emission spectra, we have extended this assessment to the broader community of fluorescence spectroscopists by involving 12 field laboratories that were randomly selected on the basis of their fluorescence measuring equipment. These laboratories performed a reference material (RM)-based fluorometer calibration with commercially available spectral fluorescence standards following a standard operating procedure that involved routine measurement conditions and the data evaluation software LINKCORR developed and provided by the Federal Institute for Materials Research and Testing (BAM). This instrument-specific emission correction curve was subsequently used for the determination of the corrected emission spectra of three test dyes, X, QS, and Y, revealing an average accuracy of 6.8% for the corrected emission spectra. This compares well with the relative standard uncertainties of 4.2% for physical standard-based spectral corrections demonstrated in the first part of this study (previous paper in this issue) involving an international group of four expert laboratories. The excellent comparability of the measurements of the field laboratories also demonstrates the effectiveness of RM-based correction procedures. KW - Fluorescence KW - Photoluminescence KW - Dye KW - Uncertainty KW - Method comparison KW - Standard KW - Method comparison KW - Spectral correction KW - Spectral fluorescence standard PY - 2012 U6 - https://doi.org/10.1021/ac203451g SN - 0003-2700 SN - 1520-6882 VL - 84 IS - 9 SP - 3899 EP - 3907 PB - American Chemical Society CY - Washington, DC AN - OPUS4-27081 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Resch-Genger, Ute A1 - Bremser, Wolfram A1 - Pfeifer, Dietmar A1 - Spieles, Monika A1 - Hoffmann, Angelika A1 - DeRose, P.C. A1 - Zwinkels, J. C. A1 - Gauthier, F. A1 - Ebert, B. A1 - Taubert, D. A1 - Monte, C. A1 - Voigt, J. A1 - Hollandt, J. A1 - Macdonald, R. T1 - State-of-the art comparability of corrected emission spectra. 1. spectral correction with physical transfer standards and spectral fluorescence standards by expert laboratories N2 - The development of fluorescence applications in the life and material sciences has proceeded largely without sufficient concern for the measurement uncertainties related to the characterization of fluorescence instruments. In this first part of a two-part series on the state-of-the-art comparability of corrected emission spectra, four National Metrology Institutes active in high-precision steady-state fluorometry performed a first comparison of fluorescence measurement capabilities by evaluating physical transfer standard (PTS)-based and reference material (RM)-based calibration methods. To identify achievable comparability and sources of error in instrument calibration, the emission spectra of three test dyes in the wavelength region from 300 to 770 nm were corrected and compared using both calibration methods. The results, obtained for typical spectrofluorometric (0°/90° transmitting) and colorimetric (45°/0° front-face) measurement geometries, demonstrated a comparability of corrected emission spectra within a relative standard uncertainty of 4.2% for PTS- and 2.4% for RM-based spectral correction when measurements and calibrations were performed under identical conditions. Moreover, the emission spectra of RMs F001 to F005, certified by BAM, Federal Institute for Materials Research and Testing, were confirmed. These RMs were subsequently used for the assessment of the comparability of RM-based corrected emission spectra of field laboratories using common commercial spectrofluorometers and routine measurement conditions in part 2 of this series (subsequent paper in this issue). KW - Fluorescence KW - Photoluminescence KW - Dye KW - Uncertainty KW - Method comparison KW - Standard KW - Method comparison KW - Spectral correction KW - Spectral fluorescence standard PY - 2012 U6 - https://doi.org/10.1021/ac2034503 SN - 0003-2700 SN - 1520-6882 VL - 84 IS - 9 SP - 3889 EP - 3898 PB - American Chemical Society CY - Washington, DC AN - OPUS4-25838 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -