Regensburg 2010 – wissenschaftliches Programm

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BP: Fachverband Biologische Physik

BP 34: Posters: New Technologies

BP 34.15: Poster

Donnerstag, 25. März 2010, 17:15–20:00, Poster B2

Applications for fluorescence lifetime imaging: Fast genomic characterization and lifetime measurements on zero-mode waveguide — •Mira Prior, Ingo Gregor, and Jörg Enderlein — Third Institute of Physics "Biophysics", Georg-August-University Göttingen

Previous studies showed that the lifetime of the DNA-intercalating dimeric cyanine dye TOTO depends on the insertion of the dye into AT or GC base pairs of the nucleic acid sequence. Utilizing this characteristic we want to develop a fast and simple method of characterizing unknown double-stranded DNA. With time-correlated single-photon counting (TCSPC) and fluorescence lifetime imaging (FLIM) we want to directly determine the lifetime of the dye YOYO in the DNA-strand depending on the insertion into an AT or GC base pair. A second application for FLIM is the detection of lifetimes of a dye on a zero-mode waveguide. The zero-mode waveguide consists of a circular aperture in an aluminum layer on a microscope slide. The detection volume is confined by the small aperture, which allows single-molecule measurements of high dye concentration in the micromolar range. TCSPC and FLIM allow us to determine the lifetime of the dye ATTO647 in dependence of the aperture diameter. The principle of the analysis of the detected photons and the identification of the single-molecules is based on a multi-exponential curve fitting and a maximum likelihood principle for the DNA-analysis. We want to analyze whether the distribution of lifetimes on the length of the ds-DNA strand correlates with the sequence of this DNA.