Dual Stimuli-Responsive Supramolecular Polypeptide-Based Hydrogel and Reverse Micellar Hydrogel Mediated by Host-Guest Chemistry

Versatile strategies are currently being discovered for the fabrication of synthetic polypeptide-based hybrid hydrogels, which have potential applications in polymer therapeutics and regenerative medicine. Herein, a new concept-the reverse micellar hydrogel-is introduced, and a versatile strategy is provided for fabricating supramolecular polypeptide-based normal micellar hydrogel and reverse micellar hydrogels from the same polypeptide-based copolymer via the cooperation of host-guest chemistry and hydrogen-bonding interactions. The supramolecular hydrogels are thoroughly characterized, and a mechanism for their self-assembly is proposed. These hydrogels can respond to dual stimuli-temperature and pH-and their mechanical and controlled drug-release properties can be tuned by the copolymer topology and the polypeptide composition. The reverse micellar hydrogel can load 10% of the anticancer drug doxorubicin hydrochloride (DOX) and sustain DOX release for 45 days, indicating that it could be useful as an injectable drug delivery system.