Aqueous micelles from supramolecular graft copolymers

Aqueous micelles have been prepared from amphiphilic supramolecular graft copolymers, in which poly(ethylene glycol) (PEG) side chains were linked to a poly(methyl methacrylate) (PMMA) backbone via ruthenium(II)-terpyridine complexes. Three different graft copolymers were investigated, in which the average number of PEG branches (constant length) and the length of the PMMA backbone were varied. The successful formation of micelles was proven by dynamic light scattering (DLS), atomic force microscopy (AFM), and transmission electron microscopy (TEM). A good agreement was found between TEM and AFM observations, which show polydisperse spherical micelles. The hydrodynamic diameter measured by DLS was much larger, suggesting the formation of aggregates. No substantial difference in the micellar characteristic features was found between the three investigated samples.