Self-threading of a poly(ethylene glycol) chain in a cyclodextrin-ring: control of the exchange dynamics by chain length.

Poly(ethylene glycol) (PEG)-substituted cyclodextrins (CDs) with different chain lengths have been synthesized. PEG-substituted CDs formed self-threading complexes in aqueous solutions, and the conformational exchange dynamics between self-threading and dethreading could be regulated by its chain length.