Although there are a number of well-characterised animal models available for testing and comparing the efficacy of iron chelators, most are expensive to operate and are not capable of providing rapid and reproducible results. The method described herein is based on the labelling of rat liver with 59Fe using rat 59Fe-ferritin. This method produces highly reproducible data of the type necessary for dose-response investigations, comparison of the efficacies of different administration routes, and structure activity studies.