Affinity Measurement Using Surface Plasmon Resonance

The change in free energy for a reaction, ΔG, can be determined from the dissociation affinity constant, K D , since ΔG is equal to RTln K D . The affinity constant provides no information on the rate of the reaction or the energy required to reach the transition state of the reaction (Fig. 1 ).   Fig. 1.  Energy vs reaction coordinates. A=analyte, L=ligand.