Jankevics, HannaPrummer, MichaelVogel, Horst2015-09-222015-09-222015-09-222006https://infoscience.epfl.ch/handle/20.500.14299/118439The present invention relates to a method for testing a substance interacting with a target molecule in a cell by fluorescence correlation spectroscopy (FCS) by adding a test substance to the cell and determining a distribution of diffusion coefficients for the fluorescently labelled target molecule. Preferably, the target molecule is a nuclear hormone receptor, e.g. the estrogen receptor.patentWO200601310935106877