Utilization of Multi-array Electrodes for Delivery of Drugs and Genes in the Mouse Skin

To take full advantage of electroporation mediated delivery of therapeutic molecules to skin, it is important to establish an efficient and safe delivery system. Current electrode systems typically induce muscle twitching and pain, which is related to the distance between the electrodes and the applied voltage. Hence, the use of non-invasive electrodes, by which the delivery of electric pulses does not damage the skin, but does successfully permeabilize the skin cells and deliver the desired molecules into them is necessary. For these purposes, a system consisting of an array of electrodes was developed and evaluated in our study. In the scope of our study, the multi-array electrodes combined with electroporation proved to be effective for the delivery of model drugs (dextran and doxorubicin) as well as plasmid DNA to the mouse skin, with minimal skin damage caused by electric pulses. Furthermore, the advantage of the multi-array electrodes is to adjust the number of addressable electrode pairs that are contained within the electrode applicator, which was also demonstrated in our study. The use of multi-arrays with adjustable pins would be a valuable approach for the delivery of genes around the skin area for wound healing as well as for peritumoral delivery for cancer gene therapy. These results suggest that electroporation with multi-array electrodes can be efficient and non-invasive skin delivery method for therapeutic drugs and genes, with less adverse side effects than other electroporation delivery systems, and with promising clinical applications.