It is challenge to deliver genes and high molecular weight drugs into mammalian cells. Viruses and liposome nanoparticles have been widely used as in vivo carriers. However, issues such as safety and low efficiency have limited their clinic applications. Physical methods such as micro-injection, gene gun, and electroporation can be used for either in vivo and/or ex vivo gene delivery. They are, however, very invasive and often provide limited efficiency. A novel device containing micro/nanoscale flow channels has been developed in our laboratory. When a programmed electric field is applied, the channels provide a focused electric field, which can realize local cell electroporation, enhance electrophoretic mobility, and provide better gene/drug confinement near the cell surface to facilitate genes or drugs transport into the cells. Using GFP and SeAP plasmid DNAs and Dextran as model materials, our results showed that this device can significantly improve drug delivery and gene expression with minimum cell damage at cell or tissue levels.