A rapid and convenient screening method to optimize elution fran affinity chranatography is described. An immunoaffinity system employing antibody bound human thyroglobulin (hTg) served as a model. Anti-hTg was complexed to polystyrene microplates adsorbed hTg. Immune complex (IC) dissociation and elution of antigen by various agents was determined by enzyme linked immunosorbent assay (ELISA). The method permits simultaneous monitoring of residual antigenicity and of possible desorption of antigen from its solid support.