[Equilibrium and kinetic parameters of interaction between peroxidase conjugates of strophanthin and anti-peroxidase antibodies].

: Interactions of three horseradish peroxidase (HRP)-strophanthin conjugates containing one, two, or three glycoside molecules (HRP-Str1, 2, or 3, respectively) with polyclonal anti-HRP antibodies were studied by homogeneous enzyme immunoassay. The total peroxidase activity of free conjugates and their immune complexes was estimated from the oxidation of o-phenylenediamine. The dissociation constants of the immune complexes and the rate constants of their dissociation and formation were determined. The equilibrium and kinetic parameters were determined for the interactions of the HRP-Str2 immune complex with anti-strophanthin and anti-HRP antibodies. The determined equilibrium and kinetic parameters of the HRP-Str interactions with anti-HRP antibodies depended on the molecular weights, sizes, and structures of the antigens studied.