TY  - JOUR
A1  - Gehne, Sören
A1  - Flehr, Roman
A1  - Kienzler, Andrea Altevogt Nee
A1  - Berg, Maik
A1  - Bannwarth, Willi
A1  - Kumke, Michael Uwe
T1  - Dye dynamics in three-color FRET samples
JF  - The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces & biophysical chemistry
N2  - Time-resolved emission data (fluorescence decay and fluorescence depolarization) of two three-color Forster resonance energy transfer (tc-FRET) systems consisting of a carbostyril donor (D), a ruthenium complex (Ru) as relay dye, and a Cy5 derivative (Cy) or, optionally, an anthraquinone quencher (Q) were carefully analyzed using advanced distribution analysis models. Thereby, it is possible to get information on the flexibility and mobility of the chromophores which are bound to double stranded (ds) DNA. Especially the distance distribution based on the analysis of the fluorescence depolarization is an attractive approach to complement data of fluorescence decay time analysis. The distance distributions extracted from the experimental data were in excellent agreement with those determined from accessible volume (AV) simulations. Moreover, the study showed that for tc-FRET systems the combination of dyes emitting on different time scales (e.g., nanoseconds vs microseconds) is highly beneficial in the distribution analysis of time-resolved luminescence data in cases where macromolecules such as DNA are involved. Here, the short lifetimes can yield information on the rotation of the dye molecule itself and the long lifetime can give insight in the overall dynamics of the macromolecule.
Y1  - 2012
U6  - https://doi.org/10.1021/jp3064273
SN  - 1520-6106
VL  - 116
IS  - 35
SP  - 10798
EP  - 10806
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Hille, Carsten
A1  - Berg, Maik
A1  - Bressel, Lena
A1  - Munzke, Dorit
A1  - Primus, Philipp
A1  - Löhmannsröben, Hans-Gerd
A1  - Dosche, Carsten
T1  - Time-domain fluorescence lifetime imaging for intracellular pH sensing in living tissues
N2  - pH sensing in living cells represents one of the most prominent topics in biochemistry and physiology. In this study we performed one-photon and two-photon time-domain fluorescence lifetime imaging with a laser-scanning microscope using the time-correlated single-photon counting technique for imaging intracellular pH levels. The suitability of different commercial fluorescence dyes for lifetime-based pH sensing is discussed on the basis of in vitro as well of in situ measurements. Although the tested dyes are suitable for intensity-based ratiometric measurements, for lifetime- based techniques in the time-domain so far only BCECF seems to meet the requirements of reliable intracellular pH recordings in living cells.
Y1  - 2008
U6  - https://doi.org/10.1007/s00216-008-2147-0
ER  -