Photocontrollable block copolymer micelles: what can we control?

Recent progress in the design and development of photocontrollable block copolymer (BCP) micelles is reviewed. By choosing an appropriate photoreaction of photochromic moieties linked to BCPs, such as photoisomerization, photocleavage and photodimerization, various types of control over polymer micelles can be achieved using light. These include either reversible or irreversible dissociation, reversible cross-linking, and reversible morphological transition of polymer micelles in response to light exposure. The design rationale for light-responsive BCPs, the underlying mechanisms of their photocontrol and the possible future development in exploring light as a powerful stimulus to control the structures or functions of BCP micelles are discussed.