Two novel non-viral gene delivery vectors: low molecular weight polyethylenimine cross-linked by (2-hydroxypropyl)-beta-cyclodextrin or (2-hydroxypropyl)-gamma-cyclodextrin

Two novel polymers of low molecular weight polyethylenimine cross-linked by (2-hydroxypropyl)-beta-cyclodextrin or (2-hydroxypropyl)c- cyclodextrin showed lower cytotoxicity and higher transfection efficiency for the delivery of plasmid DNA compared with those of polyethylenimine (PEI, 25 kDa).