Displacement curve for the binding of¹²⁵I-rhEPO to hEPO-specific magnetic beads.

The curve depicts binding of human serum EPO (○) and rhEPO (●) to monodisperse magnetic beads coated with a polyclonal anti-rhEPO antibody, and it shows the displacement of ¹²⁵I-rhEPO by increasing amounts of nonlabeled hEPO. Magnetic beads were incubated with hEPO (endogenous or recombinant) and rhEPO tracer for 48 hours under rotation at ambient temperature.