TY - CHAP A1 - Resch-Genger, Ute A1 - Hoffmann, Katrin A1 - Pauli, Jutta ED - Brahme, A. T1 - Signal-relevant properties of fluorescent labels and optical probes and their determination N2 - Luminescence techniques are among the most populär analytical and detection tools in the life Sciences (Das et al., 2012; Kobayashi et al., 2010; Lakowicz, 2006; Weissleder and Pittet, 2008). The ever-growing interest in these methods that yield fluorophore-specific quantities such as emission and excitation spectra, fluorescence quantum yields, fluorescence lifetimes, and emission anisotropies is due to their comparable ease of use; noninvasive character; potential for combining spectrally, temporally, and spatially resolved ineasurements; and suitability for multiplexing and remote sensing (Resch-Genger et al., 2005a). Moreover, fluorescence detection techniques can provide sensitivity down to the single-molecule level. As the vast majority of analytes or targets of interest are nonfluorescent and most endogenous chromophores typically display rather low fluorescence quantum yields, the tremendous analytical potential of photoluminescence techniques initiated also the development of an ever-growing number of fluorescent labels and probes as readily available tools for a broad variety of analytes and applications and the labeling of biomolecules such as oligonucleotides, antibodies, or peptides as detailed in the chapter "Fluorescent Reporters and Optical Probes: Dye Conjugation Chemistry, Spectroscopic Properties, and Design Concepts" (Berezin and Achilefu, 2010; Escobedo et al., 2010; Luo et al., 2011; Resch-Genger and Licha, 2011; Resch-Genger et al., 2008). Prominent examples of such dye-biomolecule conjugates are fluorophore-labeled secondary antibodies, for example, for immunohistochemistry or flow cytometry, and conventional contrast agents, consisting of a fluorescent reporter and a biomarker-specific biomolecule like a peptide, antibody, or antibody fragment for in vivo near-infrared (NIR) fluorescence imaging of pathological changes in the spectral window of 650-950 nm. These contrast agents are often referred to as targeted optical probes. In addition, more sophisticated Systems are increasingly emerging, the optical properties of which can be modulated selectively by Chemical or biological inputs (Elias et al., 2008; Kobayashi et al., 2011; Resch-Genger and Licha, 2011). PY - 2014 SN - 978-0-444-53632-7 DO - https://doi.org/10.1016//B978-0-444-53632-7.00408-1 VL - 4 SP - Chapter 4.02, 15 EP - 26 PB - Elsevier CY - Amsterdam AN - OPUS4-31433 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -