Study on Interaction between Polyamidoamine Dendrimers and Cu~(2+)

The effects of the generations of polyamidoamine(PAMAM)dendrimers,molar ratio of G4.0 PAMAM and Cu2+,solution pH,reaction temperature and time on the interaction of G4.0 PAMAM dendrimers with Cu2+ were studied.The results showed that the maximum absorption wavelength of PAMAM dendrimers-Cu2+ complex in aqueous solution shifted from 683 nm to 561 nm as the generation of PAMAM dendrimers varied from 3.5 to 4.0,and that a new absorption peak at 610 nm was observed as the molar ratio of G4.0 PAMAM and Cu2+ varied from 1∶10 to 1∶30.It was also found that the complex was very sensitive to solution pH.At pH 3.0,G4.0 PAMAM dendrimers could not complex with Cu2+,indicating that the bound Cu2+ could be released and that PAMAM dendrimers could be recycled.The intensity of the absorption spectrum of the complex in the visible range was enhanced with increase of the reaction temperature,but the interaction of G4.0 PAMAM dendrimers with Cu2+ was affected insignificantly by the reaction time.