Surface Plasmon Resonance

Surface Plasmon Resonance (SPR) is a real-time, label-free technique for detecting and monitoring biomolecular interactions at a sensor surface by measuring changes in the refractive index caused by ligand binding. Developed by Kretschmann in 1971 and applied to biosensing by Liedberg, Nylander, and Lundström in 1983, SPR is now a gold standard for measuring binding kinetics (association and dissociation rates) and equilibrium binding constants in protein interactions, antibody-antigen recognition, and drug discovery.