Stimuli-responsive aqueous micelles from an ABC metallo-supramolecular triblock copolymer

A metallo-supramolecular ABC triblock copolymer containing a bis(2,2':6',2-terpyridine)ruthenium(II) complex as a supramolecular connection between the constituting poly(styrene)-block-poly-(2-vinylpyridine) diblock and poly(ethylene oxide) block (PS32-b-P2VP(13)-[Ru]-PEO70) has beers prepared. This copolymer vas further utilised in order to prepare aqueous micelles consisting of a PS core, a pH-sensitive P2VP shell, and a PEO corona. The accordingly formed micelles have been characterized by a combination of dynamic light scattering, transmission electron microscopy, and atomic force microscopy. Spherical micelles and a minor fraction of bigger aggregates were observed by these three independent techniques. The pH sensitivity of the P2VP shell could be demonstrated and the reversibility of the metallo-sugramolecular complex investigated utilizing a strong competitive ligand.