Intracellular co-delivery of zinc ions and plasmid DNA for enhancing gene transfection activity

Abstract

Zinc ions, methylated poly(1-vinylimidazole) (PVIm-Me) and plasmid DNA (pDNA) have formed ternary complexes for gene delivery. The resulting Zn–PVIm-Me–pDNA complexes have delivered both Zn²⁺ ions and pDNA inside cells, leading to the nuclear translocation of the pDNA. By use of the pDNA containing a nuclear protein, NF-κB, binding sequence, the intracellular co-delivery of Zn²⁺ ions and pDNA has enhanced gene expression. These results suggest that the intracellular Zn²⁺ ions delivered by Zn–PVIm-Me–pDNA complexes activated the NF-κB, enhancing the nuclear translocation of the pDNA. In conclusion, it has been demonstrated that the Zn–PVIm-Me–pDNA complex is capable of enhancing the gene transfection activity by a synergic effect of the PVIm-Me and the co-delivered intracellular Zn²⁺ ions.