Encapsulation of metalloporphyrins improves their capacity to block the viability of the human malaria parasite Plasmodium falciparum

Synthetic metallated protoporphyrins were tested for their ability to block the cell cycle of the lethal human malaria parasite P. falciparum. Zinc(II)-protoporphyrin (Zn-PPIX) showed an antimalarial effect with an IC50 = 330 nM, which is an 80-fold increase compared to the antimalarial activity of non-encapsulated Zn-PPIX. Moreover incubation of P. falciparum infected-red blood cells with 20 μM ZnPPIX impairs the growth of the hemozoin crystal by 34%, confirming that the heme detoxification pathway is an important target for drug therapy.174