Micelles Made to Order

摘要

Covalently connecting two dis- tinct polymer segments at their ends results in the formation of a class of hybrid macromolecules called block copolymers (1,2). Placed in a solvent in which one segment is soluble and the other is not, these "amphiphilic" block copolymers will self-organize into supramolecular micelles, with insoluble cores shielded from the solvent by a corona formed by the soluble segments. The most common micellar structure consists of a spherical core shielded by radiating corona chains. Elongated cylindrical micelles (3) or bilayer vesicles (similar to liposomes) can also be realized. The structural and chemical diversity of block copolymer micelles makes them attractive for use in applicationsrnas varied as drug delivery, personal care products, and nanolithography (3,4).