Abstract: The present invention relates to a method for determining intrinsic binding parameters, such as KD, kd and ka, of an analyte to a ligand, such as a drug and a protein, a drug and a receptor, and an antibody and antigen, wherein the maximal binding response Rmax or RL and at least one binding parameter is determined at at least two different ligand surface densities present on a sensor support, and extrapolating the value of the binding parameter to ligand density=0, characterized by Rmax=0 or R1=0, to a method of selecting an analyte and/or ligand, and to the selected ligand, analyte and a sensor.