DENDRIMERS WITH HYDROPHOBIC CORES AND THE FORMATION OF SUPRAMOLECULARDENDRIMER-SURFACTANT ASSEMBLIES

The structure of a series of poly(amidoamine) dendrimers Gn(C12) gener ated from a diaminododecane core have been investigated using the phot ophysical properties of an external dye, nile red. The modified dendri mers Gn(C12) show the ability to host the hydrophobic dye, nile red, i n aqueous solution. The ability of Gn(C12) to host nile red has been c ompared to corresponding amino-core Gn(NH3) and diaminoethane-core Gn( C2) dendrimers of the same generation size. The emission of nile red i n aqueous media is significantly enhanced in the presence of Gn(C12) a nd not at all for Gn(NH3) and Gn(C2). These results imply a strong ten dency for the nile red probe to associate with the long methylene chai n of the modified dendrimers in aqueous solutions. Moreover, the inter actions of these dendrimers with anionic surfactants generate supramol ecular assemblies which greatly enhance their ability to accomodate th e nile red. Fluorescence polarization and emission as a function of pH were also studied in an effort to elucidate the interaction of the ni le red probe with the dendrimer-surfactant assemblies.