Polypeptide-shelled poly(propylene imine) dendrimers were realized by ring-opening polymerization of alpha-amino acid N-carboxyanhydrides, initiated by dendrimers as core molecules. Polypeptides with 2nd generation core were used as model compounds to investigate interior complexes between metal ion and surface-modified dendrimers. Microcalorimetric measurements outlined the formation of approximate 1:1 complexes between Cu-II and polypeptide-shelled dendrimers and the influence of polypeptide chain compositions on differential molar heats of complexation.