POTENTIAL OF BIOSENSOR TECHNOLOGY FOR THE CHARACTERIZATION OF INTERACTIONS BY QUANTITATIVE AFFINITY-CHROMATOGRAPHY

This review places the characterization of interactions by biosensor t echnology in the broader context of their study by quantitative affini ty chromatography. The general reluctance to consider biosensor-based characterization as a form of quantitative affinity chromatography on the grounds of a difference in aims of the two techniques reflects a m istaken belief that BIAcore and IAsys studies characterize the kinetic s of the chemical reaction responsible for biospecific adsorption of a soluble reactant to an immobilized form of its affinity partner. It n ow transpires that the association and dissociation rate constants the reby determined refer to thermodynamic characterization of biospecific adsorption in terms of a single-phase model in which affinity sites a re distributed uniformly throughout the liquid-phase volume accessible to the partitioning reactant-the model used for characterization of b iospecific adsorption by quantitative affinity chromatography. In that light the most important attribute of biosensor technology is its pot ential for thermodynamic characterization of biospecific adsorption by virtue of its ability to monitor complex formation directly; and henc e its potential for the characterization of interactions with affiniti es that are too strong for study by forms of quantitative affinity chr omatography that monitor complex formation on the basis of reactant de pletion from the liquid phase. Kinetic as well as thermodynamic analys es of biosensor data are described for attainment of that potential. ( C) 1998 Elsevier Science B.V. All rights reserved.