Block copolymer micelles as carriers of transition metal ions Y(III) and Cu(II) and gelation thereof

Poly(ethylene oxide)-block-poly(2-(diethylamino)ethyl methacrylate) (PEO-b-PDEAEMA) diblock copolymer was synthesized by anionic polymerization, whose molecular structure was characterized by H-1 NMR and size exclusion chromatography (SEC). The diblock copolymer self-assembled into micelles in nonacid aqueous solution with PEO and PDEAEMA as corona and core respectively. By virtue of the coordinating property of PDEAEMA block to metal ions, the resultant micelles were then used as carriers to load metal ions Y(III) and Cu(II) in the micellar core. The morphology and stability of the metal loaded micelles were characterized by dynamic light scattering (DLS), atomic force microscopy (AFM) and transmission electron microscopy (TEM). The metal loading amounts were determined by elemental analyses, UV spectrometry and titrimetric analysis. In addition, the Y(III) loaded micelles were demonstrated to complex with alpha-cyclodextrins and form supramolecular hydrogels in-situ. The metal loaded micelles and the resultant supramolecular hydrogels will have potential application for cancer internal radiotherapy. (C) 2014 Elsevier Ltd. All rights reserved.