TY - JOUR A1 - Rurack, Knut A1 - Resch-Genger, Ute T1 - Rigidization, preorientation and electronic decoupling-the "magic triangle" for the design of highly efficient fluorescent sensors and switches N2 - One of the key interests in the recent development of fluorescent molecular sensors and switches is the realization of systems that show strong signal changes as a response to the chemical trigger. Aiming at rational probe design, this article compiles and compares different promising strategies to extract those supramolecular and photophysical features that allow the construction of molecular devices suitable for efficient signaling. The examples comprise fluorescence OFF–ON as well as ON–OFF operative systems and the mechanisms, properties, and limitations of the different design concepts are discussed. PY - 2002 DO - https://doi.org/10.1039/b100604p SN - 0306-0012 SN - 1460-4744 VL - 31 IS - 2 SP - 116 EP - 127 PB - Royal Society of Chemistry CY - London AN - OPUS4-2083 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Resch-Genger, Ute A1 - Rurack, Knut A1 - Senoner, Mathias T1 - Zeitaufgelöste Fluorometrie in der Wasseranalytik PY - 1994 SN - 0341-5163 SN - 1521-3854 VL - 42 IS - 5 SP - 504 EP - 506 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-2104 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bricks, J. L. A1 - Slominskii, J. L. A1 - Kudinova, M. A. A1 - Tolmachev, A. I. A1 - Rurack, Knut A1 - Resch-Genger, Ute A1 - Rettig, W. T1 - Syntheses and photophysical properties of a series of cation-sensitive polymethine and styryl dyes N2 - The syntheses and photophysical properties of 20 cation-sensitive fluoroionophores carrying the tetraoxa monoaza 15-crown-5 receptor are described and discussed. Whereas complexation induces only weak effects for the positively charged hemicyanine probes, the closely related styryl dyes show stronger changes in their photophysical properties upon cation binding in the analytically advantageous near-infrared (NIR) region. The strongest effects in both cation-induced spectral effects and complex stability constants are observed for the uncharged probes of styryl base-type, but these probes usually absorb and emit at shorter wavelengths in the UV/VIS region. For both styryl dyes and styryl bases, in some cases cation-induced fluorescence enhancement or quenching is found. KW - Fluorescence KW - Ionophores KW - Unsymmetrical cyanines KW - Styryl dyes KW - Styryl bases PY - 2000 DO - https://doi.org/10.1016/S1010-6030(00)00208-2 SN - 1010-6030 SN - 1873-2666 VL - 132 IS - 3 SP - 193 EP - 208 PB - Elsevier CY - Lausanne AN - OPUS4-2089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rurack, Knut A1 - Unger, Brita A1 - Müller, Ralf A1 - Jancke, Harald A1 - Resch-Genger, Ute T1 - Die Strukturentwicklung von SiO2 Solen und Gelen im Vergleich mikroskopischer und makroskopischer Untersuchungsmethoden T2 - 77. Glastechnische Tagung CY - Leipzig, Deutschland DA - 2003-05-26 PY - 2003 VL - 77 SP - 101 EP - 104 PB - DGG CY - Offenbach AN - OPUS4-3121 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köster, D. A1 - Mayer-Enthart, Elke A1 - Sialelli, J. A1 - Rurack, Knut A1 - Resch-Genger, Ute A1 - Seitz, H. T1 - Hula Hoop für DNA - Eine hoch sensitive Detektionsmethode für DNA Microarrays N2 - DNA Microarrays, auch als „DNA-Chips“ bekannt, werden verwendet, um das Vorkommen von Genen bzw. Gentranskripten zu analysieren. Sie finden breite Anwendung in der Diagnostik, der Genomanalyse und bei der Erstellung von Genexpressionsprofilen. Vor der Analyse muß auf Grund der oftmals geringen Menge an Probenmaterial eine Vervielfältigung der Probe durchgeführt werden, die jedoch leicht zu Fehlern führt. Im Rahmen dieses Projektes werden zwei experimentelle Ansätze verfolgt, durch die ohne einen Verlust an Sensitivität eine Vervielfältigung der Probe vermieden werden kann, 1) das Etablieren eines RCA-basierten Microarray Assays und 2) die Optimierung des Assays für die Detektion der Fluoreszenzsignale. KW - Newsletter von GABI KW - NGFN KW - GenoMik und FUGATO mit Informationen aus der deutschen Genomforschung PY - 2008 SN - 1617-562X VL - 1 SP - 23 EP - 25 PB - DHGP CY - Berlin AN - OPUS4-17393 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Dekhtyar, M. A1 - Bricks, J. A1 - Resch-Genger, Ute A1 - Rettig, W. T1 - Quantum yield switching of fluorescence by selectively bridging single and double bonds in chalcones - involvement of two different types of conical intersections N2 - From the fluorescence properties of chalcones as a function of solvent polarity, and by the comparison to derivatives with donors and acceptors and with various selectively bridged bonds, it can be concluded that two emissive and two nonemissive states are needed to describe the fluorescence behavior. Three of these states are connected with bond twisting and lead to species with high or low dipole moment, two of them situated in the proximity of a conical intersection. KW - Fluoreszenz KW - Konische Durchschneidung PY - 1999 DO - https://doi.org/10.1021/jp992878m SN - 1089-5639 SN - 1520-5215 VL - 103 IS - 48 SP - 9626 EP - 9635 PB - Soc. CY - Washington, DC AN - OPUS4-2093 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Rettig, W. A1 - Resch-Genger, Ute T1 - Unusually high cation-induced fluorescence enhancement of a structurally simple intrinsic fluoroionophore with a donor-acceptor-donor constitution N2 - Upon cation complexation, donor–acceptor–donor–substituted intrinsic fluoroionophore 3 shows red-shifted emission spectra accompanied by an extraordinarily high fluorescence enhancement. KW - Fluoreszenz KW - Ionophor KW - Ladungstransfer PY - 2000 DO - https://doi.org/10.1039/a909899b SN - 0022-4936 SN - 0009-241x SN - 1359-7345 SN - 1364-548x VL - 2000 IS - 5 SP - 407 EP - 408 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-2091 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rurack, Knut T1 - Die Strukturentwicklung von SiO2 Solen und Gelen im Vergleich mikroskopischer und makroskopischer Untersuchungsmethoden T2 - 77. Glastechnische Tagung CY - Leipzig, Germany DA - 2003-05-26 PY - 2003 AN - OPUS4-3754 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Brita A1 - Rurack, Knut A1 - Müller, Ralf A1 - Resch-Genger, Ute A1 - Buttke, K. T1 - Effects of the Sol-Gel Processing on the Fluorescence Properties of Laser Dyes in Tetraethoxysilane Derived Matrices N2 - Two fluorescent dyes were incorporated into sol-gel derived SiO2 matrices. The dye was added to SiO2 precursors of different degrees of pre-condensation and the spectroscopic properties of the immobilized dye were measured at various aging and drying stages of the resulting gels. The significant influence of the processing parameters on the spectroscopic properties is manifested in the relative intensity of a second red shifted emission band (550–560 nm), which was observed besides the typical coumarin emission band (495 nm). The appearance of this long wavelength emission might be attributed to dye aggregation or to other reactions with the ambient matrix forced by micro porosity phenomena. KW - Sol-gel KW - Precursor chemistry KW - Fluorescence properties KW - Optical solids PY - 2000 DO - https://doi.org/10.1023/A:1008768318418 SN - 0928-0707 SN - 1573-4846 VL - 19 SP - 799 EP - 802 PB - Kluwer Academic Publ. CY - Dordrecht AN - OPUS4-1080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Resch-Genger, Ute A1 - Rurack, Knut A1 - Bricks, J.L. A1 - Slominskii, J.L. T1 - New fluorophore receptor systems for heavy metal ions: a spectroscopic study KW - Fluorescence KW - Probe KW - Cation complex KW - Ion responsive KW - Chelation enhanced PY - 1997 SN - 1053-0509 SN - 1573-4994 VL - 7 IS - 1 SP - 231S EP - 233S PB - Plenum Publ. Corp. CY - New York, NY AN - OPUS4-2100 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rurack, Knut A1 - Bricks, J. L. A1 - Slominskii, J. L. A1 - Resch-Genger, Ute ED - Dähne, S. T1 - Long wavelength emitting fluorescence probes for metal ions T2 - NATO Advanced Research Workshop on Syntheses, Optical Properties and Applications of Near-Infrared (NIR) Dyes in High Technology Fields CY - Trest', Czech Republic DA - 1997-09-24 PY - 1998 IS - 52 SP - 191 EP - 200 PB - Kluwer CY - Dordrecht AN - OPUS4-2097 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Bricks, J.L. A1 - Kachkovski, A. A1 - Resch-Genger, Ute T1 - Complexing fluorescence probes consisting of various fluorophores linked to 1-aza-15-Crown-5 KW - Fluoroinophore KW - Calcium KW - Sodium KW - Ion sensor KW - Photoinduced electron transfer PY - 1997 SN - 1053-0509 SN - 1573-4994 VL - 7 IS - 1 SP - 63S EP - 66S PB - Plenum Publ. Corp. CY - New York, NY AN - OPUS4-2101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Senoner, Mathias A1 - Resch-Genger, Ute A1 - Dähne, Siegfried T1 - Heavy metal complexes of 2,2'-bipyridyl-3,3'-diol PY - 1994 SN - 0323-598x VL - 21 SP - 683 EP - 684 PB - Akad. Verl. CY - Berlin AN - OPUS4-2103 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rurack, Knut ED - Resch-Genger, Ute ED - O.S. Wolfbeis, T1 - Fluorescence Quantum Yields:Methods of Determination and Standards N2 - The fluorescence quantum yield Φ f is a key property that characterizes the ability of a fluorophore to convert absorbed photons into emitted photons under various environmental conditions. Knowledge of it is important for the successful development of fluorometric indication and visualization methods and for the understanding of light-driven processes in the natural sciences. Φ f is a molecule- or material-related parameter and can thus significantly differ from the fraction of absorbed photons that are actually measured as the fluorescence signal of a certain sample, e.g., when the signal is modulated by reabsorption, self-quenching or polarization effects. The determination of Φ f can be performed in absolute measurements or relative to a fluorescent standard material with a known Φ f by optical or calorimetric methods. Here the different procedures and techniques are described and compared, and the suitability of a representative number of dyes that have been proposed as fluorescence reference materials in the past 25 years is discussed. Besides addressing specific issues such as low-temperature measurements and the appropriate choice of standards and measurement conditions, we conclude with recommendations for better standardization and quality management in this area. PY - 2008 SN - 978-3-540-75206-6 DO - https://doi.org/10.1007/4243_2008_019 SN - 1617-1306 N1 - Serientitel: Springer Series on Fluorescence – Series title: Springer Series on Fluorescence VL - 5 IS - Part B SP - 101 EP - 145 PB - Springer AN - OPUS4-18445 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Resch-Genger, Ute A1 - Rettig, W. T1 - Global analysis of time-resolved emission-a powerful tool for the analytical discrimination of chemically similar ZnII and CdII complexes N2 - The simultaneous analytical discrimination of spectrally very similar components with time- and wavelength-resolved fluorescence spectroscopy is demonstrated for the fluorescent probe BP(OH)2 and its complexes with the d10 metal ions CdII and ZnII in water. Whereas the absorption and emission spectra of the three components largely overlap the fluorescence lifetimes differ significantly. As a consequence, analyzing steady-state emission spectra of samples containing unknown amounts of both metal ions yields poor results for the analytical validity but the recording of fluorescence decay curves at different emission wavelengths improves the quality of the results drastically. The two techniques are compared in terms of goodness and analytical accuracy of the fit as well as analytical applicability. KW - Time-resolved KW - Fluorescence KW - ZnII KW - CdII KW - 2,2´-Bipyridyl-3,3´-diol PY - 1998 DO - https://doi.org/10.1016/S1010-6030(98)00369-4 SN - 1010-6030 SN - 1873-2666 VL - 118 IS - 3 SP - 143 EP - 149 PB - Elsevier CY - Lausanne AN - OPUS4-2096 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Kollmannsberger, M. A1 - Resch-Genger, Ute A1 - Daub, J. T1 - A selective and sensitive fluoroionophore for HgII, AgI, and CuII with virtually decoupled fluorophore and receptor units KW - Fluoreszenz KW - Ionophor PY - 2000 UR - http://pubs.acs.org/journals/jacsat/index.html SN - 0002-7863 SN - 1520-5126 VL - 122 IS - 5 SP - 968 EP - 969 PB - American Chemical Society CY - Washington, DC AN - OPUS4-2092 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Sczepan, M. A1 - Spieles, Monika A1 - Resch-Genger, Ute A1 - Rettig, W. T1 - Correlations between complex stability and charge distribution in the ground state for CaII and NaI complexes of charge transfer (CT) chromo- and fluoroionophores N2 - Several series of crown fluoro-chromo-ionophores covering a broad spectral range are investigated experimentally and compared to their theoretically studied dimethylamino (DMA) analogues. It is shown that the logarithm of the complex stability constants log KS for NaI and CaII ions do not correlate with the observed complexation-induced shift. Likewise, an unsatisfactory correlation is found between the local charge density on the amino nitrogen of the DMA dyes and log KS. However, using the charge of the whole dimethylamino group instead strongly improves this correlation. This can be understood by considering pyramidalization and hyperconjugation effects on the amino nitrogen. The observed correlation allows a novel approach to the design of fluoroionophores with optimized properties. KW - Ionophor KW - Komplex KW - Ladungsverteilung KW - Calcium KW - Natrium PY - 2000 DO - https://doi.org/10.1016/S0009-2614(00)00203-7 SN - 0009-2614 SN - 1873-4448 VL - 320 IS - 1-2 SP - 87 EP - 94 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-2090 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Bricks, J. L. A1 - Reck, Günter A1 - Radeglia, Reiner A1 - Resch-Genger, Ute T1 - Chalcone-analogue dyes emitting in the near-infrared (NIR) - influence of donor-acceptor substitution and cation complexation on their spectroscopic properties and X-ray structure N2 - The photophysical properties of several newly synthesized 1-benzothiazole-3-(4-donor)-phenyl-substituted prop-2-en-1-ones (substituted chalcones) are studied as a function of solvent polarity, temperature, and metal ion by employing steady-state and time-resolved spectroscopy. To investigate the effect of bulkiness and donor strength of the anilino moiety on the spectroscopic properties of these dyes, the spectroscopic behavior of the 4-N-dimethylamino (DMA), the 4-N-tetraoxa-monoaza-15-crown-5 (A15C5), and the 4-N-tetrathia-monoaza-15-crown-5 (AT415C5) derivatives as well as the 3-julolidino (Jul) analogue is compared. Absorption and fluorescence measurements reveal that the strength of the intramolecular charge transfer (ICT) process increases on the order of AT415C5 < A15C5 ~ DMA < Jul. The slight but significant differences between the two crowned dyes are well-supported by the results of the X-ray structure analysis, where oxa aza and thia aza crowns show essentially different geometries. For both fluoroionophores, this variation of heteroatom substitution pattern of the receptor induces specific cation selectivities. The spectroscopic effects accompanying complexation and the different binding sites are studied by steady-state and time-resolved optical spectroscopy as well as NMR spectroscopy. Whereas the probe carrying a tetraoxa monoaza 15-crown-5 receptor shows cation-induced fluorescence enhancement in the presence of alkali and alkaline-earth metal ions, its tetrathia analogue binds selectively to HgII, AgI, and CuII in acetonitrile. Moreover, an increase in fluorescence is observed for the latter probe even upon coordination to the widely known fluorescence quencher HgII. Besides receptor complexation, chelate formation in the benzothiazole-carbonyl acceptor part of these intrinsic fluorescent probes is possible, leading to a chromoionophoric signaling behavior in the near-infrared (NIR). PY - 2000 DO - https://doi.org/10.1021/jp994269k SN - 1089-5639 SN - 1520-5215 VL - 104 IS - 14 SP - 3087 EP - 3109 PB - Soc. CY - Washington, DC AN - OPUS4-2088 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Resch-Genger, Ute A1 - Kollmannsberger, M. A1 - Daub, J. A1 - Rettig, W. T1 - Design of an efficient charge-transfer processing molecular system containing a weak electron donor: spectroscopic and redox properties and cation-induced fluorescence enhancement N2 - The acceptor strength of the boron-dipyrromethene chromophore in directly linked donor–acceptor compounds can be tuned by substituents in such a way that a fast excited state charge transfer takes place even for the comparatively weak benzo crown electron donor. This leads to strong fluorescence quenching. Upon binding of cations (Na+ and K+) to the benzo crown receptor, the donor properties of the latter are further reduced, partly suppressing charge transfer. Large fluorescence enhancement factors and cation-selective fluorescence decay times result which are the basis for improved analytical application of these dyes as highly sensitive fluorescent probes. PY - 2000 DO - https://doi.org/10.1016/S0009-2614(00)01058-7 SN - 0009-2614 SN - 1873-4448 VL - 329 IS - 5-6 SP - 363 EP - 369 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-1049 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rurack, Knut A1 - Resch-Genger, Ute A1 - Rettig, W. T1 - Fluoreszenzmarker für Schwer- und Übergangsmetallionen - Selektivität durch gezieltes Rezeptordesign und ionenspezifische Fluoreszenzverstärkung T2 - Tagung "Tag der Chemie 2000" CY - Potsdam, Deutschland DA - 2000-11-08 KW - Fluoreszenzmarker KW - Schwermetalle KW - Rezeptoren PY - 2000 SP - 87 AN - OPUS4-1016 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Leiterer, Jork A1 - Grabolle, Markus A1 - Rurack, Knut A1 - Resch-Genger, Ute A1 - Ziegler, J. A1 - Nann, T. A1 - Panne, Ulrich T1 - Acoustically Levitated Droplets - A Contactless Sampling Method for Fluorescence Studies N2 - Acoustic levitation is used as a newtool to study concentration-dependent processes influorescence spectroscopy. With this technique, small amounts of liquid and solid samples can be measured without the need for sample supports or containers, which often limits signal acquisition and can even alter sample properties due to interactions with the support material. We demonstrate that, because of the small sample volume, fluorescence measurements at high concentrations of an organic dye are possible without the limitation of inner-filter effects, which hamper such experiments in conventional, cuvette-based measurements. Furthermore, we show that acoustic levitation of liquid samples provides an experimentally simple way to study distance-dependent fluorescence modulations in semiconductor nanocrystals. The evaporation of the solvent during levitation leads to a continuous increase of solute concentration and can easily be monitored by laser-induced fluorescence. KW - Acoustic levitation KW - Dyes KW - Energy transfer KW - Fluorescence KW - Quantum dots KW - Nanocrystals KW - Ultrasonic trap PY - 2008 DO - https://doi.org/10.1196/annals.1430.039 SN - 0077-8923 SN - 1749-6632 SN - 0094-8500 VL - 1130 SP - 78 EP - 84 PB - New York Academy of Sciences CY - New York, NY AN - OPUS4-17658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bierstedt, Andreas A1 - Warschat, Carsten A1 - You, Yi A1 - Rurack, Knut A1 - Riedel, Jens T1 - Stimulated Raman scattering by intracavity mixing of nanosecond laser excitation and fluorescence in acoustically levitated droplets N2 - Raman spectroscopy is becoming a commonly used, powerful tool for structural elucidation and species identification of small liquid samples, e.g. in droplet-based digital microfluidic devices. Due to the low scattering cross sections and the temporal restrictions dictated by the droplet flow, however, it depends on amplification strategies which often come at a cost. In the case of surface-enhanced Raman scattering (SERS), this can be an enhanced susceptibility towards memory effects and cross talk, whereas resonant and/or stimulated Raman techniques require higher instrumental sophistication, such as tunable lasers or the high electromagnetic field strengths which are typically provided by femtosecond lasers. Here, an alternative instrumental approach is discussed, in which stimulated Raman scattering (SRS) is achieved using the single fixed wavelength output of an inexpensive diode-pumped solid-state (DPSS) nanosecond laser. The required field strengths are realized by an effective light trapping in a resonator mode inside the interrogated droplets, while the resonant light required for the stimulation is provided by the fluorescence signal of an admixed laser dye. To elucidate the underlying optical processes, proof-of-concept experiments are conducted on acoustically levitated droplets, mimicking a highly reproducible and stable digital fluidic system. By using isotope-labeled compounds, the assignment of the emitted radiation as Raman scattering is firmly corroborated. A direct comparison reveals an amplification of the usually weak spontaneous Stokes emission by up to five orders of magnitude. Further investigation of the optical power dependence reveals the resulting gain to depend on the intensity of both, the input laser fluence and the concentration of the admixed fluorophore, leaving SRS as the only feasible amplification mechanism. While in this study stable large droplets have been studied, the underlying principles also hold true for smaller droplets, in which case significantly lower laser pulse energy is required. Since DPSS lasers are readily available with high repetition rates, the presented detection strategy bears a huge potential for fast online identification and characterization routines in digital microfluidic devices. KW - Ultrasonic levitation KW - Stimulated Raman Spectroscopy PY - 2020 DO - https://doi.org/10.1039/D0AY01504K VL - 12 IS - 42 SP - 5046 EP - 5054 PB - Royal Society of Chemistry AN - OPUS4-51566 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -