Polysaccharide-based supramolecular drug delivery systems mediated via host-guest interactions of cucurbiturils

With excellent biocompatibility and biodegradability, natural polysaccharides and their derivatives have exhibited great potential in constructing drug delivery vehicles for tissue engineering and therapeutics. Cucurbit[n]uril (CB[n])-mediated reversible crosslinking of polysaccharides possess intrinsic stimuli-responsiveness towards competitive guests and have been extensively investigated to fabricate various particles and hydrogels for multiple stimuli-responsive drug release by incorporation with other stimuli including photo, redox, and enzyme. Through host-guest interactions between CB[6] and aliphatic diamines, functional tags covalently connected with CB[6] can be readily anchored into polysaccharide-based hydrogels, realizing multiple functionalization. The rheological property and drug release profile of polysaccharide-based supramolecular hydrogels can be facilely tuned through CB[8]-mediated dynamic homo or hetero crosslinking of polysaccharides and/or other polymers. In this review, we introduce and summarize recent progress regarding polysaccharide-based supramolecular drug delivery systems mediated via host-guest interactions of CB[6] and CB[8], covering both bulk hydrogels and particular systems. At the end, possible utilization of CB[7]-based host-guest interactions in constructing polysaccharide-based drug delivery systems and future perspectives of this research direction are also discussed.