REALTIME KINETIC-ANALYSIS OF ANTIGEN-ANTIBODY INTERACTION USING SOLID-PHASE BINDING - TRANSFORMATION OF HCG-MONOCLONAL ANTIBODY COMPLEX

Kinetic constants of MAb-hCG interactions have been determined using s olid phase binding of I-125[hCG] to immobilized MAb. While association has been shown to follow the expected pattern, dissociation consists of at least two reversible steps, one with a rate constant of 0.0025 m in(-1), and a second with a rate constant of 0.00023 min(-1). Validity of affinity constant measurements in the light of the complex reactio n kinetics is discussed, A comparison between the method of surface pl asmon resonance technology (BIAcore) and solid phase binding (SPB) for determination of kinetic parameters shows that SPB provides not only a cost-effective approach for determination of realtime kinetic parame ters of macromolecular ligand-ligate interaction but also a method wit h several advantages over the BIAcore system in investigating the mech anism of antigen-antibody interaction.