Ligand Binding

Idea: In this experiment we determine the binding of a ligand
to a receptor using spectroscopic means

Biophysics Lab Course, Institute of Biophysics, Ulm University


The amino acid Trp-214 within HSA (human serum albumin) acts as a FRET donor and the ligand 3-hydroxyflavone acts as the acceptor.

Acceptor ligand is successively added and the decreasing donor fluorescence and increasing acceptor fluorescence due to FRET-complexes is recorded.

The binding affinity is investigated from both the donor-quenching and analysis of the average FRET-efficiency in a binding isotherm. The latter also gives information about the D-A distance.