Abstract: The adsorption and desorption of Immunogobulin M(IgM) antigen on the ecrystal modified with anti-IgMantibody have been continuously monitored and the immunoreaction kinetics of IgM-antigen with the anti-IgMantibody has been investigated by using the quartzcrystal microbalance methodology.Immobilization of the anti-IgMantibody to the crystal's surface was accomplished via a CNBr-activated copolymer coating of hydroxyethyl-methacrylate(HEMA) and methyl-methacrylate (MMA),The results indicated that the binding behavior of IgMon the crystal's surface was fitted for the Langmuir adsorption equation quite well.The association constant of the immunoreaction(K_ass)calculated from this equation was7.10×10⁷(mol/L)^-1.The kinetic equation of this reaction under the condition of excessive IgM antigen was derived.This equation was exactly fitted for the experimental results.The reaction rate constants (k_f) at different temperatures and the Arrhenius activation energy(E_a) of the immunoreaction in this experimental system were calculated.It was inferred that the activation energy of this immunoreaction was mainly used to overcome the hydrousenergy of the molecules of antigen and antibody.

Key words: Quartz crystal microbalance, IgM immunoreaction, Immunoreaction kinetics, Activation energy of immunoreaction