Medical applications of electroporation

In vivo electroporation, first reported in 1987, makes it possible to render cell membranes temporarily permeable to substances that otherwise would not be able to effectively enter the cell interior. Micro- or millisecond pulses of electrical field strengths exceeding the natural cellular transmembrane potential difference of approximately I V results in permeabilization ("poration") of cell membranes. This phenomenon opens up numerous applications in the medical field. Electroporative delivery of chemotherapeutic drugs into tumor cells has proven successful in clinical studies to treat malignant tumors and is nearing market Introduction in Europe. For gene therapy applications, delivery of DNA by electroporation into a variety of tissues has been shown to consistently result in a 100-1000-fold enhancement of gene expression. Other applications of electroporation discussed in this paper include intravascular delivery of drugs and genes with electroporation catheters, electroinsertion of molecules into membranes, intraocular delivery of drugs and genes, and transdermal drug delivery. The use of electroporation for drug and gene delivery in vivo is clearly gaining momentum, and new medical applications are emerging at an increasing rate.