Polymer Micelles for Drug Delivery

Polymeric micelles obtained from the self-assembly of amphiphilic block copolymers are probably one of the most common drug delivery carriers among polymeric nanoparticles.1–4 The rise of highly controlled polymerization techniques, especially processes such as ATRP5 and RAFT,6 has led to an extraordinary surge of new types of block copolymers fit for biomedical applications. Facile control over the polymer structure has also meant access to a large array of selfassembled morphologies including micelles, cylindrical micelles, and polymersomes. Micelles in particular are at the center of attention as potential drug carriers due to a core-shell structure that is highly water soluble while still maintaining a hydrophobic core suitable for hydrophobic drugs. This is crucial for many drugs since they are often rendered insoluble in water, and loading them into drug carriers can increase their solubility by several orders of magnitude.4,7