Effect of Cu2+ upon the Fluorescent Properties of Dendrimer PAMAM-FCD

Dendrimer of polyamidoamine PAMAM was modified with 2-fluorenecarboxaldehyde(FCD) to form dendrimers PAMAM-FCD of generation one, two and three, respectively. Structures and properties of PAMAM-FCD were characterized by IR, H-1 NMR and MALDI-TOF-MS, with special attention being paid to the effect Of Cu2+, on the fluorescent and UV spectra of these dendrimers. The results show that, even though Cu2+ usually behaves as a fluorescence quencher, it can significantly enhance the fluorescence of these dendrimers. Furthermore, the absorbance of PAMAM-FCD in the UV spectrum was also found to increase with the addition Of Cu2+. The disappearance of the absorbance Of Cu2+ itself suggest that coordination reaction between Cu2+ and PAMAM-FCD has occurred. These PAMAM-FCD dendrimers are promising to be the scarce material to emit blue fluorescence or as a dendrimer-copper hybrid material.