Abstract

Serum labelled with ⁵⁹Fe for ferrokinetic studies should contain only [⁵⁹Fe] transferrin. [⁵⁹Fe] ferric citrate was incubated at 37°C for up to 24 hours with sera having an excess latent iron-binding capacity. The results showed that unbound [⁵⁹Fe] ferric citrate may be present for several hours. An anion exchange resin (IRA 400 Cl⁻) column removed all the [⁵⁹Fe] ferric citrate and left only [⁵⁹Fe] transferrin in the eluate. It is suggested that all ⁵⁹Fe-labelled preparations for ferrokinetic studies should be passed through a resin column before injection.