The core-shell micelles in aqueous solutions were prepared at low CAC values (<0.1 mg · mL(-1) ) from amphiphilic graft copolymers consisting of poly(methyl methacrylate) backbone (120-165 units) with loosely grafted (17-40%) hydroxyl-capped PEG (9 vs 6 units in side chain) for drug loading. Hydrophobic indomethacin (IMC) was loaded into the micelles with content of 22-88%. Hydrodynamic diameters of particles were ranged in 110-200 nm. In vitro release experiments at various pH indicated faster releasing of IMC at pH 7.4 than that at pH 5.0. The studies on micellization, drug loading and release profiles verified the cumulative influence of hydrophilic/hydrophobic balance, degree of grafting, length of PEG side chains giving advantages in macromolecular design of nanocarriers in drug delivery.
