In this work, we have inserted the ion-heme group characterizing human blood in a class of synthetic, dendrimeric macromolecules, to evaluate a series of structural and physico-chemical properties related to the possible biological activity of these polymers. To this purpose, we have performed a complete series of investigations of five dendrimer generations both in vacuum and in water by molecular mechanics/dynamics simulations. To mimic oxygen binding, we have studied the same molecules in which the protoporphyrinic core was complexed to a Fe(II)-O(2)-hystidine residue. The main results of this study have led us to conclude that all dendrimer generations can bind oxygen stably, the fifth generation being the most affine to the myoglobin molecule, the natural carrier of blood oxygen.