Photophysical studies of the interactions of poly(amidoamine) generation zero (PAMAM G0) with copper and zinc ions

This study reports the photophysical behavior of poly(amidoamine) generation zero (PAMAM G0) in the presence of Cu(II) and Zn(II) ions in aqueous solutions using absorption and fluorescence spectroscopy. Theoretical and experimental results confirmed the presence of a strong covalent metal-ligand interaction between PAMAM G0 and copper ion that favored the formation of a ligand-metal charge transfer band coordination complex. In the case of Zn(II), no complex formation with PAMAM G0 was registered. Structure analysis identified the presence of aggregate like PAMAM G0-Zn moieties that generated an enhancement in the fluorescence emission of PAMAM G0.