Novel core−shell structured nanoassemblies are assembled by a β-cyclodextrin containing a positively charged host polymer and a hydrophobic guest polymer. The hydrophobic core of these types of assemblies serves as a nanocontainer to load and release the hydrophobic drugs, while the positively charged hydrophilic shell is able to condense the plasmid DNA and achieve its transfection/expression in osteoblast cells. These assemblies may be used as a new generation of multifunctional nanocarriers for simultaneous drug delivery and gene therapy.