Fluorescence correlation spectroscopy (FCS)
The Wolfson Bioimaging Facility supports fluorescence correlation spectroscopy with specialised hardware and software added to one of its Leica SP8 CLSM systems.
Fluorescence correlation spectroscopy is the analysis of the fluorescence fluctuations in a stationary laser excitation volume.
Typical FCS measurements include:
- concentration measurements
- diffusion and anomalous diffusion/transport coefficients
- binding interactions (ligand-receptor interactions, protein-DNA interactions, enzyme kinetics, protein-protein interactions, equilibrium constants)
- photophysics (triplet transitions/blinking/photobleaching)
- mechanics/dynamics of cellular structures
- oligomerisation, single molecule spectroscopy.
Our FCS system is part of a Leica SP8X system also equipped for STED and FLIM. Combined with STED, FCS measurements in smaller focal volume allows analysis of dynamics at higher fluorophore concentrations. Combining with fluorescence lifetime measurements allows FLCS (Fluorescence Lifetime Correlation Spectroscopy) measurements to remove scattering and increase the accuracy of derived concentrations through data filtering based on the lifetime characteristics.