Photoresponsive Capture and Release of Lectins in Multilamellar Complexes

The development of triggered release systems for delivery of peptides and proteins is critical to the success of biological drug therapies. In this paper we describe a dynamic supramolecular system able to capture and release proteins in response to light. The ternary system self-assembles in a dilute aqueous solution of three components: vesicles of amphiphilic cyclodextrin host, noncovalent cross-linkers with an azobenzene and a carbohydrate moiety, and lectins. The cross-linkers form inclusion complexes with the host vesicles, provided the azobenzene is in the <i>trans</i> state. The formation of a ternary complex with lectins requires a high density of cross-linkers on the surface of vesicles. The key innovation in this system is a photoinduced switch from a multivalent, high-affinity state that captures protein to a monovalent, low-affinity state that releases protein. By using isothermal titration calorimetry, dynamic light scattering, UV/vis spectroscopy, and cryogenic transmission electron microscopy, we demonstrate that photoinduced capture and release of lectins in dense multilamellar complexes is highly efficient, highly selective, and fully reversible