Spectroscopic studies of copper(II) and iron(II) complexes of adriamycin.

The complexes of adriamycin (ADM) with Cu(II) and Fe(II) have been studied by visible absorption, circular dichroism (CD) and fluorescence spectra, respectively. In Tris buffer at pH 7.0, either metal ions forms a single species with adriamycin: Cu(ADM)2 or Fe(ADM)3. Interaction of these two complexes with various biological molecules has been examined. It is shown that some amino acids, glutathione and albumin are able to remove the Cu(II) ion from Cu(II)-ADM complex, releasing the free drug. However, Fe(II)-ADM keeps in an undissociated form under the same conditions. The possibility of Fe(II) ADM as a new alternative drug has been discussed.