A microelectrode for electroporating an individual cell or embryo that includes a substrate with an electrically insulated surface, a first electrode adjacent to the electrically insulated surface of the substrate, a second electrode adjacent to the electrically insulated surface of the substrate and separated from the first electrode a predetermined distance so as to form a channel, and a liquid medium situated within the channel. The liquid medium is capable of fluidic transport of the cell or embryo through or into the channel and capable of supporting an electric field. The first and second electrodes include surfaces substantially orthogonal to the electrically insulated surface of the substrate with an edge length that is less than or equal to a diameter of the cell or embryo. The predetermined distance may be 50% to 200% of the diameter of the cell or embryo.