TY - JOUR A1 - Rurack, Knut A1 - Hoffmann, Katrin A1 - Al-Soufi, W. A1 - Resch-Genger, Ute T1 - 2,2'-Bipyridyl-3,3'-diol Incorporated into AlPO4-5 Crystals and Its Spectroscopic Properties as Related to Aqueous Liquid Media JF - The journal of physical chemistry / B N2 - A novel fluorescent host-guest material, molecular sieves of AlPO4-5-type doped with 2,2'-bipyridyl-3,3'-diol, was prepared and spectroscopically characterized. The composite crystals show a pronounced optical anisotropy, indicating a high degree of alignment of the guest molecules within the zeolitic pore system. A mean tilting angle of 22 was found for the orientation of the individual dye molecules in the straight channels. The corrected fluorescence emission spectra were determined, and time-resolved fluorescence studies revealed that the dye molecules are preferentially found in three different types of microenvironment. By invoking pH-dependent studies of the dye in aqueous solution, we could trace these spectroscopic features back to two main influences, coadsorbed water within AlPO4-5 pores and guest-host interactions with a few relatively weak Brnsted acid (defect) sites of the inorganic host network. PY - 2002 DO - https://doi.org/10.1021/jp0259622 SN - 1520-6106 SN - 1520-5207 SN - 1089-5647 VL - 106 IS - 38 SP - 9744 EP - 9752 PB - Soc. CY - Washington, DC AN - OPUS4-1546 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Bremser, Wolfram T1 - 2nd reference function estimation: A key element in dynamic measurement intercomparison of fluorescence T2 - PittCon T2 - PittCon CY - Chicago, IL, USA DA - 2007-02-25 PY - 2007 AN - OPUS4-16412 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Denißen, M. A1 - Nirmalananthan-Budau, Nithiya A1 - Behnke, Thomas A1 - Hoffmann, Katrin A1 - Resch-Genger, Ute A1 - Müller, T. J. J. T1 - 3-Piperazinyl propenylidene indolone merocyanines: consecutive three-component synthesis and electronic properties of solid-state luminophores with AIE properties JF - MATERIALS CHEMISTRY FRONTIERS N2 - A series of twelve 3-piperazinyl propenylidene indolone merocyanines was synthesized in a one-pot fashion using a consecutive three-component insertion-coupling-Michael addition sequence. Physicalorganic treatment of the absorption data of a consanguineous series of this library allows semiquantitative Linear Free Energy Relationships (LFERs) to be established and confirmation of the positive Absorption solvatochromicity. All Boc-substituted piperazinyl merocyanines display aggregation induced Emission (AIE), which was corroborated for two solvent systems. In particular, crystallization-induced Emission enhancement (CIEE) induced by ultrasonication could be shown for a model chromophore by confocal laser scanning microscopy (CLSM). KW - Indolone merocyanines KW - AIE KW - CIEE KW - CLSM PY - 2017 DO - https://doi.org/10.1039/c7qm00198c SN - 2052-1537 N1 - Geburtsname von Nirmalananthan-Budau, Nithiya: Nirmalananthan, N. - Birth name of Nirmalananthan-Budau, Nithiya: Nirmalananthan, N. VL - 1 IS - 10 SP - 2013 EP - 2026 AN - OPUS4-43213 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Otto, S. A1 - Grabolle, Markus A1 - Förster, C. A1 - Kreitner, C. A1 - Resch-Genger, Ute A1 - Heinze, K. T1 - [Cr(ddpd)2]3+: A molecular, water-soluble, highly NIR-emissive ruby analogue JF - Angewandte Chemie / International Edition N2 - Bright, long-lived emission from first-row transition-metal complexes is very challenging to achieve. Herein, we present a new strategy relying on the rational tuning of energy levels. With the aid of the large N-Cr-N bite angle of the tridentate ligand ddpd (N,N′-dimethyl-N,N′-dipyridine-2-ylpyridine-2,6-diamine) and its strong σ-donating capabilities, a very large ligand-field splitting could be introduced in the chromium(III) complex [Cr(ddpd)2]3+, that shifts the deactivating and photoreactive 4T2 state well above the emitting 2E state. Prevention of back-intersystem crossing from the 2E to the 4T2 state enables exceptionally high near-infrared phosphorescence quantum yields and lifetimes for this 3d metal complex. The complex [Cr(ddpd)2](BF4)3 is highly water-soluble and very stable towards thermal and photo-induced substitution reactions and can be used for fluorescence intensity- and lifetime-based oxygen sensing in the NIR. KW - Chromium complexes KW - Intersystem crossing KW - Ligand-field splitting KW - NIR luminescence KW - Photophysics PY - 2015 DO - https://doi.org/10.1002/anie.201504894 SN - 1433-7851 SN - 1521-3773 SN - 0570-0833 VL - 54 IS - 39 SP - 11572 EP - 11576 PB - Wiley-VCH CY - Weinheim AN - OPUS4-35084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - [RES]Check: Dezentrales Diagnostiksystem zur schnellen Erfassung viraler oder bakterieller Erreger respiratorischer Erkrankungen T2 - MEDICA T2 - MEDICA CY - Düsseldorf, Germany DA - 2011-11-16 PY - 2011 AN - OPUS4-25119 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nordholt, Niclas A1 - O'Hara, Kate A1 - Resch-Genger, Ute A1 - Blaskovich, M. A1 - Rühle, Bastian A1 - Schreiber, Frank T1 - A fluorescently labelled quaternary ammonium compound (NBD-DDA) to study resistance mechanisms in bacteria JF - Frontiers in microbiology N2 - Quaternary ammonium compounds (QACs) are widely used as active agents in disinfectants, antiseptics, and preservatives. Despite being in use since the 1940s, there remain multiple open questions regarding their detailed mode-of-action and the mechanisms, including phenotypic heterogeneity, that can make bacteria less susceptible to QACs. To facilitate studies on resistance mechanisms towards QACs, we synthesized a fluorescent quaternary ammonium compound, namely N-dodecyl-N,N-dimethyl-[2-[(4-nitro-2,1,3-benzoxadiazol-7-yl)amino]ethyl]azanium-iodide (NBD-DDA). NBD-DDA is readily detected by flow cytometry and fluorescence microscopy with standard GFP/FITC-settings, making it suitable for molecular and single-cell studies. As a proof-of-concept, NBD-DDA was then used to investigate resistance mechanisms which can be heterogeneous among individual bacterial cells. Our results reveal that the antimicrobial activity of NBD-DDA against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa is comparable to that of benzalkonium chloride (BAC), a widely used QAC, and benzyl-dimethyl-dodecylammonium chloride (BAC12), a mono-constituent BAC with alkyl-chain length of 12 and high structural similarity to NBD-DDA. Characteristic time-kill kinetics and increased tolerance of a BAC tolerant E. coli strain against NBD-DDA suggest that the mode of action of NBD-DDA is similar to that of BAC. As revealed by confocal laser scanning microscopy (CLSM), NBD-DDA is preferentially localized to the cell envelope of E. coli, which is a primary target of BAC and other QACs. Leveraging these findings and NBD-DDA‘s fluorescent properties, we show that reduced cellular accumulation is responsible for the evolved BAC tolerance in the BAC tolerant E. coli strain and that NBD-DDA is subject to efflux mediated by TolC. Overall, NBD-DDA’s antimicrobial activity, its fluorescent properties, and its ease of detection render it a powerful tool to study resistance mechanisms of QACs in bacteria and highlight its potential to gain detailed insights into its mode-of-action. KW - Antimicrobial resistance KW - Bacteria KW - Disinfection KW - Biocides PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-563811 DO - https://doi.org/10.3389/fmicb.2022.1023326 SN - 1664-302X IS - 13 SP - 1 EP - 13 PB - Frontiers Media CY - Lausanne AN - OPUS4-56381 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Mayer-Enthart, E. A1 - Sialelli, J. A1 - Rurack, Knut A1 - Köster, D. A1 - Seitz, H. T1 - A new detection method for the sensitive measurement of interactions on BioChips: Rolling circle amplification (RCA) T2 - DECHEMA Statusseminar Chiptechnologien T2 - DECHEMA Statusseminar Chiptechnologien CY - Frankfurt am Main, Germany DA - 2008-01-31 PY - 2008 AN - OPUS4-18550 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Resch-Genger, Ute A1 - Senoner, Mathias A1 - Dähne, Siegfried T1 - A new fluorescence probe for trace metal ions: cation dependent spectroscopic properties JF - Journal of fluorescence KW - 2,2´-Bipyridyl-3,3´-diol KW - Metal ions KW - Cation dependence KW - Fluorescence probe PY - 1993 SN - 1053-0509 SN - 1573-4994 VL - 3 IS - 3 SP - 141 EP - 143 PB - Plenum Publ. Corp. CY - New York, NY AN - OPUS4-2105 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Huang, K. A1 - Liu, H. A1 - Kraft, Marco A1 - Shikha, S. A1 - Zheng, X. A1 - Agren, H. A1 - Würth, Christian A1 - Resch-Genger, Ute A1 - Zhang, Y. T1 - A protected excitation-energy reservoir for efficient upconversion luminescence JF - Nanoscale N2 - Lanthanide-doped upconversion nanoparticles (UCNPs) are of great interest for biomedical applications. Currently, the applicability of UCNP bionanotechnology is hampered by the generally low luminescence intensity of UCNPs and inefficient energy Transfer from UCNPs to surface-bound chromophores used e.g. for photodynamic therapy or analyte sensing. In this work, we address the low-Efficiency issue by developing versatile core-Shell nanostructures, where high-concentration sensitizers and activators are confined in the core and Shell Region of representative hexagonal NaYF2:Yb,Er UCNPs. After Doping concentration optimization, the sensitizer-rich core is able to harvest/accumulate more excitation energy and generate almost one order of Magnitude higher luminescence intesity than conventional homogeneously doped nanostructures. At the same time, the activator Ions located in the Shell enable a ~6 times more efficient resonant energy Transfer from UCNPs to surface-bound acceptor dye molecules due to the short distance between donor-acceptor pairs. Our work provides new insights into the rational design of UCNPs and will greatly encrease the General applicability of upconversion nanotechnologies. KW - Fluorescence KW - Lanthanide KW - Upconversion KW - Brightness KW - Quantification KW - Nanoparticle KW - Absolute fluorometry KW - NIR KW - IR KW - Quantum yield KW - Integrating sphere spectroscopy KW - Method KW - Energy transfer KW - Shell KW - Particle architecture PY - 2017 DO - https://doi.org/10.1039/c7nr06900f SN - 2040-3372 SN - 2040-3364 VL - 10 IS - 1 SP - 250 EP - 259 PB - The Royal Society of Chemistry AN - OPUS4-43893 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 JF - Journal of the American chemical society 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 -