Construction of reverse vesicles from pseudo-graft poly(glycerol methacrylate)s via cyclodextrin-cholesterol interactions

A new type of reverse vesicle was successfully constructed from pseudo-graft amphiphilic copolymers in dichloromethane, by dint of the host-guest inclusion complexation between beta-cyclodextrins and cholesterols. Pseudo-graft copolymers were constructed from beta-cyclodextrin conjugated linear or star-shaped poly(glycerol methacrylate)s (PGMAs) of different molecular weights and a cholesterol-ended linear polylactide. The Z-average diameter of reverse vesicles was in the range of 150-350 nm with an ideal narrow polydispersity, and could be tuned by adjusting the molecular weight and branching of backbone PGMAs. Interestingly, these reverse vesicles could be transformed into organogels under specified conditions, i.e. the concentration of reverse vesicles was >1.5 g L-1, and the DCM-H2O ratio (v/v) was 8 : 1. Extraction of Congo red from the aqueous phase to the organic phase showed good cargo encapsulation capability of reverse vesicles, demonstrating their great potential as carriers or nanoreactors.