Cationic supramolecules consisting of oligoethylenimine-grafted alpha-cyclodextrins threaded on poly(ethylene oxide) for gene delivery.

In this study, three cationic polyrotaxanes composed of multiple oligoethylenimine-grafted alpha-cyclodextrin rings threaded on a poly(ethylene oxide) chain have been synthesized and characterized, and investigated for gene delivery. All three cationic polyrotaxanes could efficiently compact pDNA into small nanoparticles, with diameters ranging from 100 to 200 nm. In both BHK-21 and MES-SA cell lines, the transfection efficiency mediated by the cationic polyrotaxanes were comparable or even higher than that of branched polyethylenimine (PEI) with a molecular weight of 25 kDa, which is one of the most efficient gene-delivery vectors to date. Moreover, the cationic polyrotaxanes showed much lower cytotoxicity than branched PEI (25 kDa). Hence, these cationic poly rotaxanes have high potentials as new carriers for gene delivery. Copyright 2008 Wiley Periodicals, Inc.