@incollection{AscheBoeckmannLaueetal.2000,
author = {Asche, Hartmut and B{\"o}ckmann, Christine and Laue, Steffen and L{\"o}hmannsr{\"o}ben, Hans-Gerd and Lemke, Matthias and Schober, Lars and Reich, Oliver and L{\"u}ck, Erika and Sch{\"u}tte, Marc and Domsch, Horst and Makower, Alexander and Scheller, Frieder W. and St{\"o}cklein, Wolfgang and Wollenberger, Ursula and Schultze, Rainer and Hengstermann, Theo and Schael, Frank},
title = {Umweltforschung f{\"u}r das Land Brandenburg : Projekt Umweltanalytik / Umweltmeßtechnik / Informationssysteme},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-3862},
publisher = {Universit{\"a}t Potsdam},
pages = {176 -- 227},
year = {2000},
language = {de}
}
@incollection{LueckBalderjahnKammetal.2000,
author = {L{\"u}ck, Erika and Balderjahn, Ingo and Kamm, Birgit and Greil, Holle and Wallschl{\"a}ger, Hans-Dieter and Jessel, Beate and B{\"o}ckmann, Christine and Oberh{\"a}nsli, Roland and Soyez, Konrad and Schmeer, Ernst and Blumenstein, Oswald and Berndt, Klaus-Peter and Edeling, Thomas and Friedrich, Sabine and Kaden, Klaus and Scheller, Frieder W. and Petersen, Hans-Georg and Asche, Hartmut and Bronstert, Axel and Giest, Hartmut and Gaedke, Ursula and L{\"o}hmannsr{\"o}ben, Hans-Gerd and Jeltsch, Florian and J{\"a}nkel, Ralph and Gzik, Axel and Bork, Hans-Rudolf and Bork, Hans-Rudolf},
title = {Umweltforschung f{\"u}r das Land Brandenburg : Arbeitsgruppen und Professuren},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-3797},
publisher = {Universit{\"a}t Potsdam},
year = {2000},
language = {de}
}
@misc{HildebrandtCharbonniereZiesseletal.2006,
author = {Hildebrandt, Nico and Charbonni{\`e}re, Lo{\"i}c J. and Ziessel, Raymond F. and L{\"o}hmannsr{\"o}ben, Hans-Gerd},
title = {Quantum dots as resonance energy transfer acceptors for monitoring biological interactions},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-12213},
year = {2006},
abstract = {Quantum dots (QDs) are common as luminescing markers for imaging in biological applications because their optical properties seem to be inert against their surrounding solvent. This, together with broad and strong absorption bands and intense, sharp tuneable luminescence bands, makes them interesting candidates for methods utilizing Forster Resonance Energy Transfer (FRET), e. g. for sensitive homogeneous fluoroimmunoassays (FIA). In this work we demonstrate energy transfer from Eu3+-trisbipyridin (Eu-TBP) donors to CdSe-ZnS-QD acceptors in solutions with and without serum. The QDs are commercially available CdSe-ZnS core-shell particles emitting at 655 nm (QD655). The FRET system was achieved by the binding of the streptavidin conjugated donors with the biotin conjugated acceptors. After excitation of Eu-TBP and as result of the energy transfer, the luminescence of the QD655 acceptors also showed lengthened decay times like the donors. The energy transfer efficiency, as calculated from the decay times of the bound and the unbound components, amounted to 37\%. The Forster-radius, estimated from the absorption and emission bands, was ca. 77{\AA}. The effective binding ratio, which not only depends on the ratio of binding pairs but also on unspecific binding, was obtained from the donor emission dependent on the concentration. As serum promotes unspecific binding, the overall FRET efficiency of the assay was reduced. We conclude that QDs are good substitutes for acceptors in FRET if combined with slow decay donors like Europium. The investigation of the influence of the serum provides guidance towards improving binding properties of QD assays.},
language = {en}
}
@misc{BeckHildebrandtLoehmannsroeben2006,
author = {Beck, Michael and Hildebrandt, Niko and L{\"o}hmannsr{\"o}ben, Hans-Gerd},
title = {Quantum dots as acceptors in FRET-assays containing serum},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-9504},
year = {2006},
abstract = {Quantum dots (QDs) are common as luminescing markers for imaging in biological applications because their optical properties seem to be inert against their surrounding solvent. This, together with broad and strong absorption bands and intense, sharp tuneable luminescence bands, makes them interesting candidates for methods utilizing F{\"o}rster Resonance Energy Transfer (FRET), e. g. for sensitive homogeneous fluoroimmunoassays (FIA). In this work we demonstrate energy transfer from Eu3+-trisbipyridin (Eu-TBP) donors to CdSe-ZnS-QD acceptors in solutions with and without serum. The QDs are commercially available CdSe-ZnS core-shell particles emitting at 655 nm (QD655). The FRET system was achieved by the binding of the streptavidin conjugated donors with the biotin conjugated acceptors. After excitation of Eu-TBP and as result of the energy transfer, the luminescence of the QD655 acceptors also showed lengthened decay times like the donors. The energy transfer efficiency, as calculated from the decay times of the bound and the unbound components, amounted to 37\%. The F{\"o}rster-radius, estimated from the absorption and emission bands, was ca. 77 {\AA}. The effective binding ratio, which not only depends on the ratio of binding pairs but also on unspecific binding, was obtained from the donor emission dependent on the concentration. As serum promotes unspecific binding, the overall FRET efficiency of the assay was reduced. We conclude that QDs are good substitutes for acceptors in FRET if combined with slow decay donors like Europium. The investigation of the influence of the serum provides guidance towards improving binding properties of QD assays.},
subject = {Quantenpunkt},
language = {en}
}
@misc{DoscheLoehmannsroebenBieseretal.2002,
author = {Dosche, Carsten and L{\"o}hmannsr{\"o}ben, Hans-Gerd and Bieser, A. and Dosa, P. I. and Han, S. and Iwamoto, M. and Schleifenbaum, A. and Vollhardt, K. Peter C.},
title = {Photophysical properties of [N]phenylenes},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-11936},
year = {2002},
abstract = {In the present study, photophysical properties of [N]phenylenes were studied by means of stationary and time-resolved absorption and fluorescence spectroscopy (in THF at room temperature). For biphenylene (1) and linear [3]phenylene (2a), internal conversion (IC) with quantum yields ΦIC > 0.99 is by far the dominant mechanism of S1 state deactivation. Angular [3]phenylene (3a), the zig-zag [4]- and [5]phenylenes (3b), (3c), and the triangular [4]phenylene (4) show fluorescence emission with fluorescence quantum yieds and lifetimes between ΦF = 0.07 for (3a) and 0.21 for (3c) and τF = 20 ns for (3a) and 81 ns for (4). Also, compounds (3) and (4) exhibit triplet formation upon photoexcitation with quantum yields as high as ΦISC = 0.45 for (3c). The strong differences in the fluorescence properties and in the triplet fromation efficiencies between (1) and (2a) on one hand and (3) and (4) on the other are related to the remarkable variation of the internal conversion (IC) rate constants kIC. A tentative classification of (1) and (2a) as "fast IC compounds", with kIC > 109 s-1, and of (3) and (4) as "slow IC compounds", with kIC ≈ 107 s-1, is suggested. This classification cannot simply be related to H{\"u}ckel's rule-type concepts of aromaticity, because the group of "fast IC compounds" consists of "antiaromatic" (1) and "aromatic" (2a), and the group of "slow IC compounds" consists of "antiaromatic" (3b), (4) and "aromatic" (3a), (3c). The IC in the [N]phenylenes is discussed within the framework of the so-called energy gap law established for non-radiative processes in benzenoid hydrocarbons.},
language = {en}
}
@misc{ReichLoehmannsroebenSchael2003,
author = {Reich, Oliver and L{\"o}hmannsr{\"o}ben, Hans-Gerd and Schael, Frank},
title = {Optical sensing with photon density waves: investigation of model media},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-13147},
year = {2003},
abstract = {Investigations with frequency domain photon density waves allow elucidation of absorption and scattering properties of turbid media. The temporal and spatial propagation of intensity modulated light with frequencies up to more than 1 GHz can be described by the P1 approximation to the Boltzmann transport equation. In this study, we establish requirements for the appropriate choice of turbid model media and characterize mixtures of isosulfan blue as absorber and polystyrene beads as scatterer. For these model media, the independent determination of absorption and reduced scattering coefficients over large absorber and scatterer concentration ranges is demonstrated with a frequency domain photon density wave spectrometer employing intensity and phase measurements at various modulation frequencies.},
language = {en}
}
@misc{LoehmannsroebenKantorKumkeetal.2005,
author = {L{\"o}hmannsr{\"o}ben, Hans-Gerd and Kantor, Zoltan and Kumke, Michael Uwe and Schm{\"a}lzlin, Elmar and Reich, Oliver},
title = {OPQS - optische Prozess- und Qualit{\"a}ts-Sensorik},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-13205},
year = {2005},
abstract = {Im vorliegenden Beitrag wird an Hand dreier Beispiele der Einsatz von optischer Sensorik zur Produktcharakterisierung dargestellt, n{\"a}mlich Untersuchungen zum O2-Gehalt in Fruchts{\"a}ften, zur Isotopiesignatur von CO2 in Mineralw{\"a}ssern und zu Lichtstreueigenschaften eines Sonnenschutzmittels. Inhalt: Bestimmung von O2 mit Lumineszenzsonden Isotopenselektive Bestimmung von CO2 mit TDLAS Optische Charakterisierung stark streuender Materialien mit Photonendichtewellen},
language = {de}
}
@misc{EngelhardKumkeLoehmannsroeben2006,
author = {Engelhard, Sonja and Kumke, Michael Uwe and L{\"o}hmannsr{\"o}ben, Hans-Gerd},
title = {OPQS - optical process and quality sensing : exemplary applications in the beerbrewing and polyurethane foaming processes},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-12191},
year = {2006},
abstract = {Optical methods play an important role in process analytical technologies (PAT). Four examples of optical process and quality sensing (OPQS) are presented, which are based on three important experimental techniques: near-infrared absorption, luminescence quenching, and a novel method, photon density wave (PDW) spectroscopy. These are used to evaluate four process and quality parameters related to beer brewing and polyurethane (PU) foaming processes: the ethanol content and the oxygen (O2) content in beer, the biomass in a bioreactor, and the cellular structures of PU foam produced in a pilot production plant.},
language = {en}
}
@misc{HoernerLauLoehmannsroeben2004,
author = {H{\"o}rner, Gerald and Lau, Steffen and L{\"o}hmannsr{\"o}ben, Hans-Gerd},
title = {NIR-diode laser spectroscopy for isotope-selective sensing of soil-respired carbon dioxide},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-10148},
year = {2004},
abstract = {The performance of a home-built tunable diode laser (TDL) spectrometer has been optimized regarding multi-line detection of carbon dioxide in natural gases. In the regime of the (3001)III ← (000) band of 12CO2 around 1.6 μm, the dominating isotope species 12CO2, 13CO2, and 12C18O16O were detected simultaneously. In contrast to most established techniques, selective measurements are performed without any sample preparation. This is possible since the CO2 detection is free of interference from water, ubiquitous in natural gases. Detection limits in the range of a few ppmv were obtained for each species utilizing wavelength modulation (WM) spectroscopy with balanced detection in a long-path absorption cell set-up. Linear calibration plots cover a dynamic range of four orders of magnitude, allowing for quantitative CO2 detection in various samples, like soil and breath gas. High isotopic resolution enables the excellent selectivity, sensitivity, and stability of the chosen analytical concept. The obtained isotopic resolution of typically ± 1.0 per mille and ± 1.5 per mille (for 3 vol. \% and 0.7 vol. \% of CO2, respectively) offers a promising analytical tool for isotope-ratio determination of carbon dioxide in soil gas. Preliminary experiments on soil respiration for the first time combine the on-line quantification of the overall carbon dioxide content with an optode sensor and isotopic determination (TDL system) of natural gas species.},
subject = {Kohlendioxid},
language = {en}
}
@misc{LoehmannsroebenBeckHildebrandtetal.2006,
author = {L{\"o}hmannsr{\"o}ben, Hans-Gerd and Beck, Michael and Hildebrandt, Niko and Schm{\"a}lzlin, Elmar and van Dongen, Joost T.},
title = {New challenges in biophotonics : laser-based fluoroimmuno analysis and in-vivo optical oxygen monitoring},
url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-10120},
year = {2006},
abstract = {Two examples of our biophotonic research utilizing nanoparticles are presented, namely laser-based fluoroimmuno analysis and in-vivo optical oxygen monitoring. Results of the work include significantly enhanced sensitivity of a homogeneous fluorescence immunoassay and markedly improved spatial resolution of oxygen gradients in root nodules of a legume species.},
subject = {Sauerstoff},
language = {en}
}