Superhelices with Designed Helical Structures and Temperature-Stimulated Chirality Transitions

The synthesis of multicomponent superhelices with determined chirality has been realized. By adding water to polymer solution in organic solvents (tetrahydrofuran/ N,N'-dimethylformamide, THF/DMF), poly(gamma-benzyl L-glutamate)block-poly(ethylene glycol) (PBLG-b-PEG) are able to pack orderly around the surface of PBLG homopolymer bundles with designed helical structures, e.g., right-handed and left-handed, depending on THF/DMF ratio and temperature. A systematic investigation leads to the construction of a temperature organic solvent composition phase diagram. Before the organic solvents were totally removed, the chirality of the assemblies can be reversibly switched using temperature stimulus. This temperature-stimulated chirality transition of polypeptide superhelices is unprecedented. Circular dichroism