A tolerable and minimally invasive skin electroporation device

An electroporation device capable of delivering to a subject a tolerable electrical potential to layers of epidermal tissue between stratum corneum and basal layers that results in electroporation of cells in said epidermal tissue, comprising:

• a voltage generator;
• and
• an array having a plurality of needle electrodes in electrical communication with the voltage generator;
• wherein each one of the plurality of needle electrodes is spaced apart from each adjacent needle electrode at a spacing distance of about 0.5 mm to about 2.5 mm;
• wherein the voltage generator delivers via the plurality of needle electrodes an electrical potential of about 0.1 volts to about 70 volts to the epidermal tissue;
• and
• wherein each of the plurality of needle electrodes defines a central axis and a distal end, wherein the distal end defines a trocar tip having a sharp point and a plurality of planar surfaces that extend distally to the sharp point, wherein the plurality of planar surfaces are oriented, respectively, at generally blunt angles between 10 degrees from the central axis and substantially perpendicular to the central axis, and
• wherein the generally blunt angles and the sharp point of the trocar tip of each needle electrode and the spacing distance collectively allow the plurality of needle electrodes to 1) penetrate the layers of the epidermal tissue between stratum corneum and basal layers at depths of 0.1 mm or less, and 2) deliver the electrical potential from the voltage generator to the layers of epidermal tissue between stratum corneum and basal layers such that at least a majority of the electroporation of cells occurs in cells of stratum granulosum.