ZnO QD@PMAA-co-PDMAEMA nonviral vector for plasmid DNA delivery and bioimaging.

Low cytotoxic ZnO quantum dot-based nonviral vectors with the dual functions of delivering plasmid DNA and labeling cells were fabricated by capping the surface of ZnO QD with poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA), which was synthesized in situ by radical polymerization. The polycation-modified ZnO QDs were capable of condensing plasmid DNA into nanocomplexes (Qdotplexes) loaded with ZnO QDs emitting strong yellow luminescence under UV light. The Qdotplexes could mediate an efficient transfer of plasmid DNA into COS-7 cells with much lower cytotoxicity, meanwhile allowing real-time imaging of gene transfection.