Preparation of fullerene-shell dendrimer-core nanoconjugates

Generation 4 amine-terminated polyamidoamine dendrimer (PAMAM G4) was allowed to react with an excess of buckminsterfullerene (C-60) to form a nanoconjugate containing a PAMAM core and C60 shell. The PAMAM-C-60 conjugate was characterized by MALDI-TOF, TGA, UV-vis, and IR spectroscopy. Approximately thirty shell fullerenes surround each dendrimer core. The conjugates catalyze photooxidation of thioanisole by generation of singlet oxygen (O-1(2)). The oxidation reactions occur in both organic and aqueous solvents, but the reactivity is enhanced in aqueous solution, possibly due to a nanoreactor effect resulting from diffusion of hydrophobic reactant molecules into dendrimer cavities.(1)