Supramolecular Self-assembly of Monoend-functionalized Methoxy Poly(ethylene glycol) and α-Cyclodextrin: From Micelles to Hydrogel

An effective strategy was developed to fabricate a supramolecular hydrogel with the complexation of alpha-cyclodextrins (alpha-CDs) and monoend-functionalized low molecular weight methoxy poly(ethylene glycol) (mPEG, Mn=2000) micelles. Hydrophobic cinnamic acid was immobilized on methoxy poly(ethylene glycol) via L-lysine as linker to prepare amphiphilic mPEG. The monoend-functionalized mPEG self-assembled micelles in aqueous solution. The size and size distribution of the micelles were tested by dynamic laser scattering (DLS). The morphology of the micelles was observed by SEM, TEM and AFM. The critical micelle concentration (CMC) was tested and it was 42.5 mg/L. The monodisperse micelles had core-shell structure and the mean diameter was around 40 nanometers. alpha-cyclodextrins were added in the suspension of micelles to form supramolecular hydrogel with the polypseudorotaxanes complexation. Hydrophilic drug doxorubicin hydrochloride was used as model drug to study the release profile. The results showed that the hydrogel was a promising carrier for drug delivery.