Polymeric Nanocarriers Based on Cyclodextrins for Drug Delivery: Host-Guest Interaction as Stimuli Responsive Linker.

Stimuli responsive polymers have been extensively studied as nanocarriers for drug delivery systems (DDSs), especially those based on supramolecular interactions. Cyclodextrin (CD) is one kind of widely applied host molecule, and the host-guest interactions between CD and different counterparts can respond to different stimuli and thus can be applied as responsive linkers for polymeric DDSs. In this review, the polymeric nanocarriers based on the host-guest interactions between CD and ferrocene, azobenzene, and benzimidazole as DDSs are summarized, with redox, light, and pH sensitivity, respectively. The mechanisms for the stimuli responsive ability of the linkers, the application of them for construction of DDSs with different polymer structures, and the controlled release behaviors have been focused. In addition, the outlook and challenge of these systems are discussed.