Berlin 2001 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

AMPD: EPS AMPD

AMPD 3: Sitzung 3

AMPD 3.5: Talk

Tuesday, April 3, 2001, 15:00–15:25, H105

Biophysics on a single molecule scale: applications of fluorescence correlation spectroscopy — •Petra Schwille — Experimentelle Biophysik, MPI f. biophysikalische Chemie, Am Fassberg 11, D-37077 Goettingen

The basic principle of fluorescence correlation spectroscopy (FCS) on a system of fluorescent molecules is the analysis of minute spontaneous deviations from thermodynamic equilibrium that give rise to fluctuations in the fluorescence emission. As a requirement, simultaneously observed ensembles have to be restricted down to very low numbers, which is conveniently realized by confocal optics, generating measurement volumes of less than a femtoliter in size. With a dynamic range of 100 ns to several seconds, FCS analysis provides access to a multitude of parameters such as local concentrations, mobility coefficients, association- and dissociation constants, isomerization rates, as well as enzyme activity. As a noninvasive method, FCS can be easily applied to the dynamic study of intracellular and membrane-bound fluorophores on a single molecule scale with a spatial precision of less than 500 nm.