Compensation for Loss of Ligand Activity in Surface Plasmon Resonance Experiments

Anal Biochem. 2002 Jul 15;306(2):228-36. doi: 10.1006/abio.2002.5716.


The determination of equilibrium binding constants is an important aspect of the analysis of protein-protein interactions. In recent years surface plasmon resonance experiments (e.g., with a BIAcore instrument) have provided a valuable experimental approach to determining such constants. The standard method is based on measuring amounts of analyte bound at equilibrium for different analyte concentrations. During the course of a typical surface plasmon resonance experiment the measured equilibrium levels for a given analyte concentration often decrease. This appears to be due to a loss of activity of the protein coupled to the sensor chip or other phenomena. The loss in signal can lead to an erroneous determination of the equilibrium constant. A data analysis approach is introduced that aims to compensate for the loss of activity so that its influence on the results of the experiments is reduced.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Immunoglobulin Fab Fragments
  • Kinetics
  • Ligands*
  • Muramidase / immunology
  • Muramidase / metabolism*
  • Surface Plasmon Resonance*


  • Immunoglobulin Fab Fragments
  • Ligands
  • Muramidase