Biocompatible amphiphilic hyperbranched nanocapsules with a functional core: Synergistic encapsulation and asynchronous release properties towards multi-guest molecules

To achieve an encapsulation-release property towards multi-guest molecules, amphiphilic hyperbranched nanocapsules (AHN) consisting of a functional hyperbranched poly(β-cyclodextrin) [HBP(β-CD)] core and a methoxy polyethylene glycol shell was first constructed by click chemistry. The encapsulation-release capacity and corresponding mechanism of AHN towards multi-guest molecules were investigated by fluorescence and UV-vis spectroscopy. The results indicated that the encapsulation-release properties of AHN were pH dependent and can be applied to multi-guest systems. The multi-guest encapsulation capacity of AHN was derived from the synergistic encapsulation phenomenon of different guest molecules and the molecular recognition property of the HBP(β-CD) core. Compared with single-guest systems, AHN displays a sustained release characteristic accompanied by an "asynchronous release phenomenon" in multi-guest release systems. The release rate can also be effectively controlled because of the molecular recognition property of the HBP(β-CD) core. Both in vitro cell apoptosis and in vivo systematic toxicity assays confirmed that AHN possessed good biocompatibility.