Affinity of antimalarial drugs for stacked haematin linked on sepharose

The affinity to haematin of antimalarial drugs and of some closely related compounds has been measured by the use of a polymeric haematin linked to an agarose gel. Haematin-drug interaction shows a low specificity and does not exhibit the sharp structure-activity relationship observed in the biological activities of the compounds. It is suggested that a chloroquine-haematin interaction does not explain the biological properties of this antimalarial, although it constitutes a necessary step in the concentration of the drug in the parasitized erythrocyte.